diff --git a/modules/common/src/main/scala/docspell/common/EmptyTrashArgs.scala b/modules/common/src/main/scala/docspell/common/EmptyTrashArgs.scala
index d0436bb7..8e76d2d5 100644
--- a/modules/common/src/main/scala/docspell/common/EmptyTrashArgs.scala
+++ b/modules/common/src/main/scala/docspell/common/EmptyTrashArgs.scala
@@ -33,7 +33,7 @@ object EmptyTrashArgs {
 
   val taskName = Ident.unsafe("empty-trash")
 
-  val defaultSchedule = CalEvent.unsafe("*-*-1/7 03:00:00")
+  val defaultSchedule = CalEvent.unsafe("*-*-1/7 03:00:00 UTC")
 
   def periodicTaskId(coll: Ident): Ident =
     Ident.unsafe(s"docspell") / taskName / coll
diff --git a/modules/common/src/main/scala/docspell/common/Timestamp.scala b/modules/common/src/main/scala/docspell/common/Timestamp.scala
index c056c2a8..e72ada64 100644
--- a/modules/common/src/main/scala/docspell/common/Timestamp.scala
+++ b/modules/common/src/main/scala/docspell/common/Timestamp.scala
@@ -6,10 +6,8 @@
 
 package docspell.common
 
-import java.time.LocalDateTime
-import java.time.ZonedDateTime
 import java.time.temporal.ChronoUnit
-import java.time.{Instant, LocalDate, ZoneId}
+import java.time.{Duration => _, _}
 
 import cats.effect.Sync
 
@@ -57,7 +55,7 @@ case class Timestamp(value: Instant) {
 }
 
 object Timestamp {
-  val UTC = ZoneId.of("UTC")
+  val UTC: ZoneId = ZoneOffset.UTC
 
   val Epoch = Timestamp(Instant.EPOCH)
 
diff --git a/modules/joex/src/main/resources/reference.conf b/modules/joex/src/main/resources/reference.conf
index 5bb7bacf..8516c916 100644
--- a/modules/joex/src/main/resources/reference.conf
+++ b/modules/joex/src/main/resources/reference.conf
@@ -144,7 +144,7 @@ docspell.joex {
 
     # When the house keeping tasks execute. Default is to run every
     # week.
-    schedule = "Sun *-*-* 00:00:00"
+    schedule = "Sun *-*-* 00:00:00 UTC"
 
     # This task removes invitation keys that have been created but not
     # used. The timespan here must be greater than the `invite-time'
@@ -209,8 +209,9 @@ docspell.joex {
     test-run = false
 
     # When the update check should execute. Default is to run every
-    # week.
-    schedule = "Sun *-*-* 00:00:00"
+    # week. You can specify a time zone identifier, like
+    # 'Europe/Berlin' at the end.
+    schedule = "Sun *-*-* 00:00:00 UTC"
 
     # An account id in form of `collective/user` (or just `user` if
     # collective and user name are the same). This user account must
diff --git a/modules/webapp/src/main/elm/App/Update.elm b/modules/webapp/src/main/elm/App/Update.elm
index 88542bd5..e052010f 100644
--- a/modules/webapp/src/main/elm/App/Update.elm
+++ b/modules/webapp/src/main/elm/App/Update.elm
@@ -566,7 +566,7 @@ updateCollSettings texts lmsg model =
     let
         ( lm, lc, ls ) =
             Page.CollectiveSettings.Update.update texts.collectiveSettings
-                model.flags
+                (modelEnv model)
                 lmsg
                 model.collSettingsModel
     in
diff --git a/modules/webapp/src/main/elm/Comp/CalEventInput.elm b/modules/webapp/src/main/elm/Comp/CalEventInput.elm
index 6cd881ef..24cb0121 100644
--- a/modules/webapp/src/main/elm/Comp/CalEventInput.elm
+++ b/modules/webapp/src/main/elm/Comp/CalEventInput.elm
@@ -18,6 +18,7 @@ import Api.Model.CalEventCheck exposing (CalEventCheck)
 import Api.Model.CalEventCheckResult exposing (CalEventCheckResult)
 import Data.CalEvent exposing (CalEvent)
 import Data.Flags exposing (Flags)
+import Data.TimeZone exposing (TimeZone)
 import Data.Validated exposing (Validated(..))
 import Html exposing (..)
 import Html.Attributes exposing (..)
@@ -109,8 +110,8 @@ isCheckError model =
             False
 
 
-update : Flags -> Maybe CalEvent -> Msg -> Model -> ( Model, Cmd Msg, Maybe CalEvent )
-update flags mev msg model =
+update : Flags -> TimeZone -> Maybe CalEvent -> Msg -> Model -> ( Model, Cmd Msg, Maybe CalEvent )
+update flags tz mev msg model =
     let
         ev =
             Maybe.withDefault model.inner mev
@@ -153,7 +154,7 @@ update flags mev msg model =
             ( m
             , Cmd.none
             , if res.success then
-                Just event
+                Just { event | timeZone = tz }
 
               else
                 Nothing
diff --git a/modules/webapp/src/main/elm/Comp/ClassifierSettingsForm.elm b/modules/webapp/src/main/elm/Comp/ClassifierSettingsForm.elm
index cac96061..f4dd6129 100644
--- a/modules/webapp/src/main/elm/Comp/ClassifierSettingsForm.elm
+++ b/modules/webapp/src/main/elm/Comp/ClassifierSettingsForm.elm
@@ -26,6 +26,7 @@ import Data.DropdownStyle as DS
 import Data.Flags exposing (Flags)
 import Data.ListType exposing (ListType)
 import Data.TagOrder
+import Data.TimeZone exposing (TimeZone)
 import Data.UiSettings exposing (UiSettings)
 import Html exposing (..)
 import Html.Attributes exposing (..)
@@ -111,8 +112,8 @@ getSettings model =
         model.schedule
 
 
-update : Flags -> Msg -> Model -> ( Model, Cmd Msg )
-update flags msg model =
+update : Flags -> TimeZone -> Msg -> Model -> ( Model, Cmd Msg )
+update flags tz msg model =
     case msg of
         GetTagsResp (Ok tl) ->
             let
@@ -123,7 +124,7 @@ update flags msg model =
                 lm =
                     Comp.Dropdown.SetOptions categories
             in
-            update flags (CategoryListMsg lm) model
+            update flags tz (CategoryListMsg lm) model
 
         GetTagsResp (Err _) ->
             ( model, Cmd.none )
@@ -133,6 +134,7 @@ update flags msg model =
                 ( cm, cc, ce ) =
                     Comp.CalEventInput.update
                         flags
+                        tz
                         model.schedule
                         lmsg
                         model.scheduleModel
diff --git a/modules/webapp/src/main/elm/Comp/CollectiveSettingsForm.elm b/modules/webapp/src/main/elm/Comp/CollectiveSettingsForm.elm
index f1bf41a9..43bf6259 100644
--- a/modules/webapp/src/main/elm/Comp/CollectiveSettingsForm.elm
+++ b/modules/webapp/src/main/elm/Comp/CollectiveSettingsForm.elm
@@ -26,6 +26,7 @@ import Comp.StringListInput
 import Data.DropdownStyle as DS
 import Data.Flags exposing (Flags)
 import Data.Language exposing (Language)
+import Data.TimeZone exposing (TimeZone)
 import Data.UiSettings exposing (UiSettings)
 import Html exposing (..)
 import Html.Attributes exposing (..)
@@ -143,8 +144,8 @@ type Msg
     | PasswordMsg Comp.StringListInput.Msg
 
 
-update : Flags -> Msg -> Model -> ( Model, Cmd Msg, Maybe CollectiveSettings )
-update flags msg model =
+update : Flags -> TimeZone -> Msg -> Model -> ( Model, Cmd Msg, Maybe CollectiveSettings )
+update flags tz msg model =
     case msg of
         LangDropdownMsg m ->
             let
@@ -207,7 +208,7 @@ update flags msg model =
         ClassifierSettingMsg lmsg ->
             let
                 ( cm, cc ) =
-                    Comp.ClassifierSettingsForm.update flags lmsg model.classifierModel
+                    Comp.ClassifierSettingsForm.update flags tz lmsg model.classifierModel
             in
             ( { model
                 | classifierModel = cm
@@ -219,7 +220,7 @@ update flags msg model =
         EmptyTrashMsg lmsg ->
             let
                 ( cm, cc ) =
-                    Comp.EmptyTrashForm.update flags lmsg model.emptyTrashModel
+                    Comp.EmptyTrashForm.update flags tz lmsg model.emptyTrashModel
             in
             ( { model
                 | emptyTrashModel = cm
diff --git a/modules/webapp/src/main/elm/Comp/DueItemsTaskForm.elm b/modules/webapp/src/main/elm/Comp/DueItemsTaskForm.elm
index fe9268ce..fa32908d 100644
--- a/modules/webapp/src/main/elm/Comp/DueItemsTaskForm.elm
+++ b/modules/webapp/src/main/elm/Comp/DueItemsTaskForm.elm
@@ -29,6 +29,7 @@ import Data.CalEvent exposing (CalEvent)
 import Data.DropdownStyle as DS
 import Data.Flags exposing (Flags)
 import Data.TagOrder
+import Data.TimeZone exposing (TimeZone)
 import Data.UiSettings exposing (UiSettings)
 import Data.Validated exposing (Validated(..))
 import Html exposing (..)
@@ -237,8 +238,8 @@ withValidSettings mkcmd model =
             )
 
 
-update : Flags -> Msg -> Model -> ( Model, Action, Cmd Msg )
-update flags msg model =
+update : Flags -> TimeZone -> Msg -> Model -> ( Model, Action, Cmd Msg )
+update flags tz msg model =
     case msg of
         ChannelMsg lm ->
             let
@@ -254,6 +255,7 @@ update flags msg model =
             let
                 ( cm, cc, cs ) =
                     Comp.CalEventInput.update flags
+                        tz
                         model.schedule
                         lmsg
                         model.scheduleModel
diff --git a/modules/webapp/src/main/elm/Comp/DueItemsTaskManage.elm b/modules/webapp/src/main/elm/Comp/DueItemsTaskManage.elm
index 346482e2..fea5f130 100644
--- a/modules/webapp/src/main/elm/Comp/DueItemsTaskManage.elm
+++ b/modules/webapp/src/main/elm/Comp/DueItemsTaskManage.elm
@@ -20,6 +20,7 @@ import Comp.DueItemsTaskForm
 import Comp.DueItemsTaskList
 import Comp.MenuBar as MB
 import Data.Flags exposing (Flags)
+import Data.TimeZone exposing (TimeZone)
 import Data.UiSettings exposing (UiSettings)
 import Html exposing (..)
 import Html.Attributes exposing (..)
@@ -81,8 +82,8 @@ init flags =
 --- Update
 
 
-update : Flags -> Msg -> Model -> ( Model, Cmd Msg )
-update flags msg model =
+update : Flags -> TimeZone -> Msg -> Model -> ( Model, Cmd Msg )
+update flags tz msg model =
     case msg of
         GetDataResp (Ok items) ->
             ( { model
@@ -126,7 +127,7 @@ update flags msg model =
                 Just dm ->
                     let
                         ( mm, action, mc ) =
-                            Comp.DueItemsTaskForm.update flags lm dm
+                            Comp.DueItemsTaskForm.update flags tz lm dm
 
                         ( model_, cmd_ ) =
                             case action of
diff --git a/modules/webapp/src/main/elm/Comp/EmptyTrashForm.elm b/modules/webapp/src/main/elm/Comp/EmptyTrashForm.elm
index a65fcc89..89237a5f 100644
--- a/modules/webapp/src/main/elm/Comp/EmptyTrashForm.elm
+++ b/modules/webapp/src/main/elm/Comp/EmptyTrashForm.elm
@@ -19,6 +19,7 @@ import Comp.CalEventInput
 import Comp.IntField
 import Data.CalEvent exposing (CalEvent)
 import Data.Flags exposing (Flags)
+import Data.TimeZone exposing (TimeZone)
 import Data.UiSettings exposing (UiSettings)
 import Html exposing (..)
 import Html.Attributes exposing (..)
@@ -81,14 +82,15 @@ getSettings model =
         model.minAgeDays
 
 
-update : Flags -> Msg -> Model -> ( Model, Cmd Msg )
-update flags msg model =
+update : Flags -> TimeZone -> Msg -> Model -> ( Model, Cmd Msg )
+update flags tz msg model =
     case msg of
         ScheduleMsg lmsg ->
             let
                 ( cm, cc, ce ) =
                     Comp.CalEventInput.update
                         flags
+                        tz
                         model.schedule
                         lmsg
                         model.scheduleModel
diff --git a/modules/webapp/src/main/elm/Comp/PeriodicQueryTaskForm.elm b/modules/webapp/src/main/elm/Comp/PeriodicQueryTaskForm.elm
index c6fa1ee8..90d861af 100644
--- a/modules/webapp/src/main/elm/Comp/PeriodicQueryTaskForm.elm
+++ b/modules/webapp/src/main/elm/Comp/PeriodicQueryTaskForm.elm
@@ -25,6 +25,7 @@ import Comp.MenuBar as MB
 import Comp.PowerSearchInput
 import Data.CalEvent exposing (CalEvent)
 import Data.Flags exposing (Flags)
+import Data.TimeZone exposing (TimeZone)
 import Data.UiSettings exposing (UiSettings)
 import Data.Validated exposing (Validated(..))
 import Html exposing (..)
@@ -254,13 +255,14 @@ withValidSettings mkcmd model =
             }
 
 
-update : Flags -> Msg -> Model -> UpdateResult
-update flags msg model =
+update : Flags -> TimeZone -> Msg -> Model -> UpdateResult
+update flags tz msg model =
     case msg of
         CalEventMsg lmsg ->
             let
                 ( cm, cc, cs ) =
                     Comp.CalEventInput.update flags
+                        tz
                         model.schedule
                         lmsg
                         model.scheduleModel
diff --git a/modules/webapp/src/main/elm/Comp/PeriodicQueryTaskManage.elm b/modules/webapp/src/main/elm/Comp/PeriodicQueryTaskManage.elm
index 5f2192ca..91855b7d 100644
--- a/modules/webapp/src/main/elm/Comp/PeriodicQueryTaskManage.elm
+++ b/modules/webapp/src/main/elm/Comp/PeriodicQueryTaskManage.elm
@@ -20,6 +20,7 @@ import Comp.MenuBar as MB
 import Comp.PeriodicQueryTaskForm
 import Comp.PeriodicQueryTaskList
 import Data.Flags exposing (Flags)
+import Data.TimeZone exposing (TimeZone)
 import Data.UiSettings exposing (UiSettings)
 import Html exposing (..)
 import Html.Attributes exposing (..)
@@ -81,8 +82,8 @@ init flags =
 --- Update
 
 
-update : Flags -> Msg -> Model -> ( Model, Cmd Msg, Sub Msg )
-update flags msg model =
+update : Flags -> TimeZone -> Msg -> Model -> ( Model, Cmd Msg, Sub Msg )
+update flags tz msg model =
     case msg of
         GetDataResp (Ok items) ->
             ( { model
@@ -130,7 +131,7 @@ update flags msg model =
                     let
                         --( mm, action, mc ) =
                         result =
-                            Comp.PeriodicQueryTaskForm.update flags lm dm
+                            Comp.PeriodicQueryTaskForm.update flags tz lm dm
 
                         ( model_, cmd_ ) =
                             case result.action of
diff --git a/modules/webapp/src/main/elm/Comp/ScanMailboxForm.elm b/modules/webapp/src/main/elm/Comp/ScanMailboxForm.elm
index 2c12cc58..2bd9ff2d 100644
--- a/modules/webapp/src/main/elm/Comp/ScanMailboxForm.elm
+++ b/modules/webapp/src/main/elm/Comp/ScanMailboxForm.elm
@@ -40,6 +40,7 @@ import Data.Flags exposing (Flags)
 import Data.FolderOrder
 import Data.Language exposing (Language)
 import Data.TagOrder
+import Data.TimeZone exposing (TimeZone)
 import Data.UiSettings exposing (UiSettings)
 import Data.Validated exposing (Validated(..))
 import Html exposing (..)
@@ -183,7 +184,7 @@ initWith flags s =
                 |> Maybe.withDefault []
 
         ( nm, _, nc ) =
-            update flags (ConnMsg (Comp.Dropdown.SetSelection imap)) im
+            update flags Data.TimeZone.utc (ConnMsg (Comp.Dropdown.SetSelection imap)) im
 
         newSchedule =
             Data.CalEvent.fromEvent s.schedule
@@ -354,13 +355,14 @@ withValidSettings mkAction model =
             )
 
 
-update : Flags -> Msg -> Model -> ( Model, Action, Cmd Msg )
-update flags msg model =
+update : Flags -> TimeZone -> Msg -> Model -> ( Model, Action, Cmd Msg )
+update flags tz msg model =
     case msg of
         CalEventMsg lmsg ->
             let
                 ( cm, cc, cs ) =
                     Comp.CalEventInput.update flags
+                        tz
                         model.schedule
                         lmsg
                         model.scheduleModel
@@ -585,8 +587,8 @@ update flags msg model =
                     ( a, NoAction, b )
             in
             Util.Update.andThen1
-                [ update flags (FolderDropdownMsg opts) >> removeAction
-                , update flags (FolderDropdownMsg (Comp.Dropdown.SetSelection sel)) >> removeAction
+                [ update flags tz (FolderDropdownMsg opts) >> removeAction
+                , update flags tz (FolderDropdownMsg (Comp.Dropdown.SetSelection sel)) >> removeAction
                 ]
                 model_
                 |> addNoAction
diff --git a/modules/webapp/src/main/elm/Comp/ScanMailboxManage.elm b/modules/webapp/src/main/elm/Comp/ScanMailboxManage.elm
index 88c7d998..3720f8c1 100644
--- a/modules/webapp/src/main/elm/Comp/ScanMailboxManage.elm
+++ b/modules/webapp/src/main/elm/Comp/ScanMailboxManage.elm
@@ -21,6 +21,7 @@ import Comp.MenuBar as MB
 import Comp.ScanMailboxForm
 import Comp.ScanMailboxList
 import Data.Flags exposing (Flags)
+import Data.TimeZone exposing (TimeZone)
 import Data.UiSettings exposing (UiSettings)
 import Html exposing (..)
 import Html.Attributes exposing (..)
@@ -82,8 +83,8 @@ init flags =
 --- Update
 
 
-update : Flags -> Msg -> Model -> ( Model, Cmd Msg )
-update flags msg model =
+update : Flags -> TimeZone -> Msg -> Model -> ( Model, Cmd Msg )
+update flags tz msg model =
     case msg of
         GetDataResp (Ok res) ->
             ( { model
@@ -127,7 +128,7 @@ update flags msg model =
                 Just dm ->
                     let
                         ( mm, action, mc ) =
-                            Comp.ScanMailboxForm.update flags lm dm
+                            Comp.ScanMailboxForm.update flags tz lm dm
 
                         ( model_, cmd_ ) =
                             case action of
diff --git a/modules/webapp/src/main/elm/Comp/UiSettingsForm.elm b/modules/webapp/src/main/elm/Comp/UiSettingsForm.elm
index 23d5d827..2c8106c6 100644
--- a/modules/webapp/src/main/elm/Comp/UiSettingsForm.elm
+++ b/modules/webapp/src/main/elm/Comp/UiSettingsForm.elm
@@ -19,6 +19,7 @@ import Api
 import Api.Model.TagList exposing (TagList)
 import Comp.BasicSizeField
 import Comp.ColorTagger
+import Comp.Dropdown
 import Comp.FieldListSelect
 import Comp.FixedDropdown
 import Comp.IntField
@@ -32,7 +33,7 @@ import Data.Flags exposing (Flags)
 import Data.ItemTemplate as IT exposing (ItemTemplate)
 import Data.Pdf exposing (PdfMode)
 import Data.TagOrder
-import Data.TimeZone
+import Data.TimeZone exposing (TimeZone)
 import Data.UiSettings exposing (ItemPattern, StoredUiSettings, UiSettings)
 import Dict exposing (Dict)
 import Html exposing (..)
@@ -75,6 +76,7 @@ type alias Model =
     , powerSearchEnabled : Bool
     , uiLangModel : Comp.FixedDropdown.Model UiLanguage
     , uiLang : UiLanguage
+    , timezoneDropdown : Comp.Dropdown.Model String
     , openTabs : Set String
     , defaults : UiSettings
     }
@@ -170,6 +172,11 @@ initModel flags storedSettings defaults =
     , uiLang = settings.uiLang
     , uiLangModel =
         Comp.FixedDropdown.init Messages.UiLanguage.all
+    , timezoneDropdown =
+        Comp.Dropdown.makeSingleList
+            { options = Data.TimeZone.listAll
+            , selected = Just (Data.TimeZone.toName settings.timeZone)
+            }
     , openTabs = Set.empty
     , defaults = defaults
     }
@@ -209,6 +216,7 @@ type Msg
     | TogglePowerSearch
     | UiLangMsg (Comp.FixedDropdown.Msg UiLanguage)
     | PdfModeMsg (Comp.FixedDropdown.Msg PdfMode)
+    | TimeZoneMsg (Comp.Dropdown.Msg String)
     | ToggleAllTabs
     | ResetTab AkkordionTab
 
@@ -599,6 +607,27 @@ update flags sett msg model =
             in
             ( { nm | openTabs = model.openTabs }, Just newSettings )
 
+        TimeZoneMsg lm ->
+            let
+                ( tm, tcmd ) =
+                    Comp.Dropdown.update lm model.timezoneDropdown
+
+                tz =
+                    if Comp.Dropdown.isDropdownChangeMsg lm then
+                        Comp.Dropdown.getSelected tm |> List.head
+
+                    else
+                        sett.timeZone
+
+                newSett =
+                    if sett.timeZone == tz then
+                        Nothing
+
+                    else
+                        Just { sett | timeZone = tz }
+            in
+            ( { model | timezoneDropdown = tm }, newSett )
+
 
 
 --- View2
@@ -670,6 +699,9 @@ settingFormTabs texts flags _ model =
                 [ i [ class "fa fa-eraser mr-1" ] []
                 , text texts.resetLabel
                 ]
+
+        uiSettings =
+            Data.UiSettings.defaults
     in
     [ { name = akkordionTabName GeneralTab
       , title = texts.general
@@ -695,6 +727,22 @@ settingFormTabs texts flags _ model =
                         model.uiLangModel
                     )
                 ]
+            , div [ class "mb-4" ]
+                [ label [ class S.inputLabel ] [ text "Timezone" ]
+                , Html.map TimeZoneMsg
+                    (Comp.Dropdown.view2
+                        { makeOption = \s -> { text = s, additional = "" }
+                        , placeholder = ""
+                        , labelColor = \_ -> \_ -> ""
+                        , style = DS.mainStyle
+                        }
+                        uiSettings
+                        model.timezoneDropdown
+                    )
+                , span [ class "opacity-75 text-sm" ]
+                    [ text "Used to format date-time values."
+                    ]
+                ]
             ]
       }
     , { name = akkordionTabName SearchTab
diff --git a/modules/webapp/src/main/elm/Data/CalEvent.elm b/modules/webapp/src/main/elm/Data/CalEvent.elm
index db9307f1..6453f703 100644
--- a/modules/webapp/src/main/elm/Data/CalEvent.elm
+++ b/modules/webapp/src/main/elm/Data/CalEvent.elm
@@ -12,6 +12,7 @@ module Data.CalEvent exposing
     , makeEvent
     )
 
+import Data.TimeZone exposing (TimeZone)
 import Util.Maybe
 
 
@@ -22,12 +23,13 @@ type alias CalEvent =
     , day : String
     , hour : String
     , minute : String
+    , timeZone : TimeZone
     }
 
 
 everyMonth : CalEvent
 everyMonth =
-    CalEvent Nothing "*" "*" "01" "00" "00"
+    CalEvent Nothing "*" "*" "01" "00" "00" Data.TimeZone.utc
 
 
 makeEvent : CalEvent -> String
@@ -43,6 +45,8 @@ makeEvent ev =
                 ++ ev.hour
                 ++ ":"
                 ++ ev.minute
+                ++ " "
+                ++ Data.TimeZone.toName ev.timeZone
     in
     case ev.weekday of
         Just wd ->
@@ -60,18 +64,40 @@ fromEvent str =
 
         parts =
             String.split " " str
+
+        foldChanges : List (CalEvent -> Maybe CalEvent) -> Maybe CalEvent
+        foldChanges list =
+            List.foldl (\fmc -> \c -> Maybe.andThen fmc c) (Just init) list
     in
     case parts of
-        wd :: date :: time :: [] ->
-            Maybe.andThen
-                (fromDate date)
-                (fromTime time init)
-                |> Maybe.map (withWeekday wd)
+        wd :: date :: time :: tz :: [] ->
+            foldChanges
+                [ fromWeekDays wd
+                , fromDate date
+                , fromTime time
+                , fromTimeZone tz
+                ]
+
+        a :: b :: c :: [] ->
+            if startsWithWeekday a then
+                foldChanges
+                    [ fromWeekDays a
+                    , fromDate b
+                    , fromTime c
+                    ]
+
+            else
+                foldChanges
+                    [ fromDate a
+                    , fromTime b
+                    , fromTimeZone c
+                    ]
 
         date :: time :: [] ->
-            Maybe.andThen
-                (fromDate date)
-                (fromTime time init)
+            foldChanges
+                [ fromDate date
+                , fromTime time
+                ]
 
         _ ->
             Nothing
@@ -109,6 +135,31 @@ fromTime time ev =
             Nothing
 
 
+fromTimeZone : String -> CalEvent -> Maybe CalEvent
+fromTimeZone tzStr ev =
+    Data.TimeZone.get tzStr
+        |> Maybe.map (\tz -> { ev | timeZone = tz })
+
+
+fromWeekDays : String -> CalEvent -> Maybe CalEvent
+fromWeekDays str ce =
+    if startsWithWeekday str then
+        Just (withWeekday str ce)
+
+    else
+        Nothing
+
+
 withWeekday : String -> CalEvent -> CalEvent
 withWeekday wd ev =
     { ev | weekday = Util.Maybe.fromString wd }
+
+
+weekDays : List String
+weekDays =
+    [ "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun" ]
+
+
+startsWithWeekday : String -> Bool
+startsWithWeekday str =
+    List.any (\a -> String.startsWith a str) weekDays
diff --git a/modules/webapp/src/main/elm/Page/CollectiveSettings/Update.elm b/modules/webapp/src/main/elm/Page/CollectiveSettings/Update.elm
index 519971c0..49f376eb 100644
--- a/modules/webapp/src/main/elm/Page/CollectiveSettings/Update.elm
+++ b/modules/webapp/src/main/elm/Page/CollectiveSettings/Update.elm
@@ -12,13 +12,14 @@ import Comp.CollectiveSettingsForm
 import Comp.ShareManage
 import Comp.SourceManage
 import Comp.UserManage
-import Data.Flags exposing (Flags)
+import Data.Environment as Env
+import Data.Flags
 import Messages.Page.CollectiveSettings exposing (Texts)
 import Page.CollectiveSettings.Data exposing (..)
 
 
-update : Texts -> Flags -> Msg -> Model -> ( Model, Cmd Msg, Sub Msg )
-update texts flags msg model =
+update : Texts -> Env.Update -> Msg -> Model -> ( Model, Cmd Msg, Sub Msg )
+update texts env msg model =
     case msg of
         SetTab t ->
             let
@@ -27,45 +28,45 @@ update texts flags msg model =
             in
             case t of
                 SourceTab ->
-                    update texts flags (SourceMsg Comp.SourceManage.LoadSources) m
+                    update texts env (SourceMsg Comp.SourceManage.LoadSources) m
 
                 UserTab ->
-                    update texts flags (UserMsg Comp.UserManage.LoadUsers) m
+                    update texts env (UserMsg Comp.UserManage.LoadUsers) m
 
                 InsightsTab ->
-                    update texts flags Init m
+                    update texts env Init m
 
                 SettingsTab ->
-                    update texts flags Init m
+                    update texts env Init m
 
                 ShareTab ->
-                    update texts flags (ShareMsg Comp.ShareManage.loadShares) m
+                    update texts env (ShareMsg Comp.ShareManage.loadShares) m
 
         SourceMsg m ->
             let
                 ( m2, c2 ) =
-                    Comp.SourceManage.update flags m model.sourceModel
+                    Comp.SourceManage.update env.flags m model.sourceModel
             in
             ( { model | sourceModel = m2 }, Cmd.map SourceMsg c2, Sub.none )
 
         ShareMsg lm ->
             let
                 ( sm, sc, ss ) =
-                    Comp.ShareManage.update texts.shareManage flags lm model.shareModel
+                    Comp.ShareManage.update texts.shareManage env.flags lm model.shareModel
             in
             ( { model | shareModel = sm }, Cmd.map ShareMsg sc, Sub.map ShareMsg ss )
 
         UserMsg m ->
             let
                 ( m2, c2 ) =
-                    Comp.UserManage.update flags m model.userModel
+                    Comp.UserManage.update env.flags m model.userModel
             in
             ( { model | userModel = m2 }, Cmd.map UserMsg c2, Sub.none )
 
         SettingsFormMsg m ->
             let
                 ( m2, c2, msett ) =
-                    Comp.CollectiveSettingsForm.update flags m model.settingsModel
+                    Comp.CollectiveSettingsForm.update env.flags env.settings.timeZone m model.settingsModel
 
                 cmd =
                     case msett of
@@ -73,7 +74,7 @@ update texts flags msg model =
                             Cmd.none
 
                         Just sett ->
-                            Api.setCollectiveSettings flags sett SubmitResp
+                            Api.setCollectiveSettings env.flags sett SubmitResp
             in
             ( { model | settingsModel = m2, formState = InitialState }
             , Cmd.batch [ cmd, Cmd.map SettingsFormMsg c2 ]
@@ -83,8 +84,8 @@ update texts flags msg model =
         Init ->
             ( { model | formState = InitialState }
             , Cmd.batch
-                [ Api.getInsights flags GetInsightsResp
-                , Api.getCollectiveSettings flags CollectiveSettingsResp
+                [ Api.getInsights env.flags GetInsightsResp
+                , Api.getCollectiveSettings env.flags CollectiveSettingsResp
                 ]
             , Sub.none
             )
@@ -98,7 +99,7 @@ update texts flags msg model =
         CollectiveSettingsResp (Ok data) ->
             let
                 ( cm, cc ) =
-                    Comp.CollectiveSettingsForm.init flags data
+                    Comp.CollectiveSettingsForm.init env.flags data
             in
             ( { model | settingsModel = cm }
             , Cmd.map SettingsFormMsg cc
diff --git a/modules/webapp/src/main/elm/Page/Dashboard/Update.elm b/modules/webapp/src/main/elm/Page/Dashboard/Update.elm
index f0988cc5..a4e1072b 100644
--- a/modules/webapp/src/main/elm/Page/Dashboard/Update.elm
+++ b/modules/webapp/src/main/elm/Page/Dashboard/Update.elm
@@ -270,7 +270,7 @@ update texts settings navKey flags msg model =
                 PeriodicQuery pqm ->
                     let
                         ( pqm_, pqc, pqs ) =
-                            Comp.PeriodicQueryTaskManage.update flags lm pqm
+                            Comp.PeriodicQueryTaskManage.update flags settings.timeZone lm pqm
                     in
                     ( { model | content = PeriodicQuery pqm_ }
                     , Cmd.map PeriodicQueryMsg pqc
diff --git a/modules/webapp/src/main/elm/Page/UserSettings/Update.elm b/modules/webapp/src/main/elm/Page/UserSettings/Update.elm
index eec01a4e..8810593b 100644
--- a/modules/webapp/src/main/elm/Page/UserSettings/Update.elm
+++ b/modules/webapp/src/main/elm/Page/UserSettings/Update.elm
@@ -161,7 +161,7 @@ update flags settings msg model =
         NotificationMsg lm ->
             let
                 ( m2, c2 ) =
-                    Comp.DueItemsTaskManage.update flags lm model.notificationModel
+                    Comp.DueItemsTaskManage.update flags settings.timeZone lm model.notificationModel
             in
             { model = { model | notificationModel = m2 }
             , cmd = Cmd.map NotificationMsg c2
@@ -172,7 +172,7 @@ update flags settings msg model =
         ScanMailboxMsg lm ->
             let
                 ( m2, c2 ) =
-                    Comp.ScanMailboxManage.update flags lm model.scanMailboxModel
+                    Comp.ScanMailboxManage.update flags settings.timeZone lm model.scanMailboxModel
             in
             { model = { model | scanMailboxModel = m2 }
             , cmd = Cmd.map ScanMailboxMsg c2
@@ -227,7 +227,7 @@ update flags settings msg model =
         PeriodicQueryMsg lm ->
             let
                 ( pqm, pqc, pqs ) =
-                    Comp.PeriodicQueryTaskManage.update flags lm model.periodicQueryModel
+                    Comp.PeriodicQueryTaskManage.update flags settings.timeZone lm model.periodicQueryModel
             in
             { model = { model | periodicQueryModel = pqm }
             , cmd = Cmd.map PeriodicQueryMsg pqc
diff --git a/nix/module-joex.nix b/nix/module-joex.nix
index b387df16..ca7bbfc4 100644
--- a/nix/module-joex.nix
+++ b/nix/module-joex.nix
@@ -48,7 +48,7 @@ let
       wakeup-period = "10 minutes";
     };
     house-keeping = {
-      schedule = "Sun *-*-* 00:00:00";
+      schedule = "Sun *-*-* 00:00:00 UTC";
       cleanup-invites = {
         enabled = true;
         older-than = "30 days";
@@ -70,7 +70,7 @@ let
     update-check = {
       enabled = false;
       test-run = false;
-      schedule = "Sun *-*-* 00:00:00";
+      schedule = "Sun *-*-* 00:00:00 UTC";
       sender-account = "";
       smtp-id = "";
       recipients = [];
diff --git a/tools/start-local/start-local.sh b/tools/start-local/start-local.sh
index be2ff816..f04b123f 100755
--- a/tools/start-local/start-local.sh
+++ b/tools/start-local/start-local.sh
@@ -114,7 +114,7 @@ docspell.joex {
     retry-delay = "10 seconds"
   }
   house-keeping {
-    schedule = "*-*-* 01:00:00"
+    schedule = "*-*-* 01:00:00 UTC"
     cleanup-invites = {
       older-than = "10 days"
     }