Why calendar api does not create last day of recurrence?

Question

When I'm trying to create recurring event, the last day of recurrence is not being created. However, it is only when I provide startDateTime later than 3AM, if earlier everything works.

For example: this below does not create

start: { dateTime: '2022-07-13T03:04:00', timeZone: 'Europe/Kiev' },

How it looks in calendar ( incorrect request with time 3:04AM )

And this one creates

start: { dateTime: '2022-07-13T03:00:00', timeZone: 'Europe/Kiev' },

How it looks in calendar ( working request with time 3AM)

I think it is allocated to my timezone, which is just +3

This below is not working request

{
  summary: 'Draft #0',
  creator: { displayName: 'Test' },
  start: { dateTime: '2022-07-13T03:04:00', timeZone: 'Europe/Kiev' },
  end: { dateTime: '2022-07-13T23:58:00', timeZone: 'Europe/Kiev' },
  recurrence: [
    'EXDATE;VALUE=DATE:20220713',
    'RRULE:FREQ=DAILY;UNTIL=20220719;BYDAY=MO,TU,WE,TH,FR,SA,SU'
  ]
}

If we change in this request start.dateTime to 0-3AM everything is fine.

What shall I do in order to create this one last day?

Answer 1

Google Support Answered:

Status: Won't Fix (Intended Behavior) Hello,

This behavior is being closed as intended.

Please note that UNTIL instructs that ideally the events should be created only before that time or if the times are coinciding, the UNTIL is the last occurrence of that event. No event would be created after the UNTIL threshold is reached.

For Kiev, the timezone is UTC+0300 For events which start at 03:00 or before, the last day of the recurring event does get created. For events which start after 0300, the event is NOT created since the UNTIL parameter restricts the creation. Configure the UNTIL timezone to use the last event's required start time.

To be able to make an event on 20220719, you can configure the UNTIL clause as UNTIL=20220719T030400Z

Regards