If the duration time off is greater than or equal to 1 day, then it should be displayed as a whole day event. Now it's not a case and can be misleading. Moreover, this change increases querycount for the following reason: When we create allday calendar event, on top of usual queries - "calendar_event"."stop_date" and "calendar_event"."start_date" are read. Note, start_date and end_date are only set for allday events. task-3103848 closes odoo/odoo#113865 Signed-off-by: Sofie Gvaladze (sgv) <sgv@odoo.com>