- calendar.event.start and stop are expecting datetime and not date.
Now, if 'All Day' event, start time = 00h00 and stop time = 23h59m59s
- when switching from all day event to not all day event, due to
stop time = 23h59m59s, the rounding for duration leads to make the stop
pass to the next day (00h00). each time you switch between all day and
not all day, the duiration is incremented by 24h.
We remove 1 sec to event stop time to avoid this.