Check multiple dates in range

HI,

I want to have a formula to check if the start date and finish date are correct.

For it to be correct, the start date (for example on Strategic) on P50 should be equal or less than the P50 and start date of P50 should be equal or less than start date of P90. Similarly, P50 finish date should be more or equal to base finish date and P90 finish date should be more or equal to the P50 finish date.

This should also accordingly apply for the dates of concept, delivery readiness delivery and finalisation.


How can we set up formula for this?