Event repeat date incorrect when changing start date

• Type: Bug
• Status: Closed
• Resolution: No Longer Reproducible
• Affects Version/s: 7.0.0 DXP SP6, 7.0.0 DXP FP40, 7.0.X, Master
• Fix Version/s: 7.0.X, 7.1.X, Master
• Component/s: Calendar
• Labels: None
• Story Points: 1
• Fix Priority: 4

Steps to reproduce:

1. Add a calendar to the page.
2. Click Add Event button.
3. Type in title and choose a start date, for example: 03/02/2018.
4. Click Repeat checkbox.
5. In the pop-up window, choose weekly of the repeat field, click Done.
6. Change the start date to a day ahead, for example: 03/01/2018.
7. Change the start date to two days later, for example: 03/03/2018..
8. Change the start date back to the date that you choose in step 2, for example: 03/02/2018.

Expected result:
The event repeats once a week.
Actual result:
The event repeats three times a week.