Repeat End-Start period cannot be added twice with the same repeat interval to calendar assigned to job/order

Current Situation

• The period is not added if we add two Repeat End-Start periods to the same calendar assigned to job/order with same interval.

How to reproduce

• Create a calendar
• Add the working day calendar to a job or order
• Add the period for to this calendar.
• Use Repeat End-Start with a interval like:
  • Begin: 07:00 End: 09:00 and repeat interval is of 00:01.
• Add another Repeat End-Start period to the same calendar like assigned to the job/order:
  • Begin: 11:00 End: 12:00 and repeat interval is of 00:01.
• The second period will not be added.

Desired Behavior

• The period should be added even if we add two Repeat End-Start periods to a calendar assigned to job/order with same interval.