### Steps to reproduce

1. Have 2 phases (A, B) with dates set

2. Clear phase A finish date

3. Clear phase B start date

4. Begin of the insertionOnEnd of the insertion Begin of the deletion SetEnd of the deletion phase Begin of the insertionA, setEnd of the insertion Begin of the deletion AEnd of the deletion the Begin of the insertionfinishEnd of the insertion Begin of the deletion wholeEnd of the deletion date Begin of the deletion rangeEnd of the deletion to an

1. **earlier date** than phase Begin of the insertionB'sEnd of the insertion Begin of the deletion BEnd of the deletion finish Begin of the insertiondate.End of the insertion Begin of the deletion date set in step #2.End of the deletion

2. Begin of the insertion**laterEnd of the insertion Begin of the deletion **latterEnd of the deletion date** than phase Begin of the insertionB'sEnd of the insertion Begin of the deletion BEnd of the deletion finish Begin of the insertiondate.End of the insertion Begin of the deletion date set in step #2.End of the deletion

5. Open the Phase B edit dialog. It will display the default start date and the finish date, but the start date field is not yet set, so it will not appear as completely set.

6. Clicking save on phase B without any modifications will either:

1. set the range correctly. (If 4.a is chosen)

2. display an error message on the disabled start date. (If 4.b is chosen)


### What is the buggy behavior?

* In case **4.a** the range appears to be complete on **phase B**, however the start date is not yet stored and we display the default start date only.

* In case **4.b** the same issue as 4.a on **phase B**, plus it will display a validation error message on the start date being later than the finish date.


### What is the expected behavior?

1. Begin of the deletion \[OPEN\]End of the deletion In case Begin of the insertion**4.a:**

1. SetEnd of the insertion Begin of the deletion **4.a** not sure, maybe setEnd of the deletion the start date of Begin of the deletion phaseEnd of the deletion B Begin of the insertiontoEnd of the insertion Begin of the deletion duringEnd of the deletion the Begin of the insertionnext working dayEnd of the insertion Begin of the deletion reschedule happeningEnd of the deletion after Begin of the insertionthe finish date ofEnd of the insertion Begin of the deletion saving phaseEnd of the deletion A. Begin of the insertion

End of the insertion Begin of the deletion

End of the deletion 2. Begin of the insertionThe duration is updated accordingly (finish date - start date of B).

3. The values are stored in the database.

2. End of the insertion Begin of the deletion \[OPEN\]End of the deletion In case Begin of the insertion**4.b:**

1. SetEnd of the insertion Begin of the deletion **4.b** displayEnd of the deletion the Begin of the insertionstart date of B toEnd of the insertion Begin of the deletion error message onEnd of the deletion the Begin of the insertionnext working day after theEnd of the insertion finish Begin of the insertiondate of A

2. SetEnd of the insertion Begin of the deletion date, becauseEnd of the deletion the Begin of the insertionfinishEnd of the insertion Begin of the deletion startEnd of the deletion date Begin of the insertionof B to the next working day after the finish date of A.

3. The durationEnd of the insertion is Begin of the deletion not editable. But since weEnd of the deletion set Begin of the insertionto 1.

4. The values are stored inEnd of the insertion the Begin of the insertiondatabase.

3. In case 4.a/4.b are done not with the finish date on A but with theEnd of the insertion start date Begin of the insertiononly, the behaviour should be just the same. Meaning if only the start date of phase A is set and not the finish date, itEnd of the insertion Begin of the deletion automatically, weEnd of the deletion will Begin of the insertionhaveEnd of the insertion Begin of the deletion createEnd of the deletion an Begin of the insertionaffect onEnd of the insertion Begin of the deletion invalid phase, so not sure what would beEnd of the deletion the Begin of the insertiondates of B.End of the insertion Begin of the deletion right solution here.End of the deletion


Begin of the insertionThe behaviour should by that be identical to how scheduling happens for work packages.

<br>

End of the insertion ### Screenshots and other files

1. **Setting earlier dates on Phase A than Phase B finish date.**
<img class="op-uc-image op-uc-image_inline" src="/api/v3/attachments/649692/content">

2. **Setting latter dates on Phase A than Phase B finish date.**

<img class="op-uc-image op-uc-image_inline" src="/api/v3/attachments/649694/content">


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