The check UpdateEvent runs on its changes: a time change must say how to read the times. Without
IsAllDay and TimeZone a provider would write the event back as a timed event in UTC, so a
moved all-day event would turn timed and a local one would change zone. A message when they are
missing, null otherwise.
The check
UpdateEventruns on its changes: a time change must say how to read the times. WithoutIsAllDayandTimeZonea provider would write the event back as a timed event in UTC, so a moved all-day event would turn timed and a local one would change zone. A message when they are missing,nullotherwise.