Currently, the Change calendar displays change requests based on the following fields:

1. Planned start or Planned start date – when the change request is planned to start.
2. Planned end or Planned end date – when the change request is planned to finish.
3. Actual start or Change start date – the actual date and time the change started.
4. Actual end or Change completion date – the actual date and time the change ended.

Suggestion

Implement the ability to select other date/time custom fields to work with the Change calendar.