Dynamic task calendar that accounts for holidays

[estephenkim]

I'm developing a dynamic calendar (not shown) that sources its tasks from a task schedule (see enclosed screen capture). In the task schedule, the user enters the decision date in cell D1 and the task schedule populates the decision date in B13. The other dates are workdays relative to the decision date.

Depending on the decision date, there may be a holiday among the workdays leading to the decision date, in which case any task corresponding to the holiday (and all previous tasks) will need to shift back to the previous workday. In other words, due to the holiday on Feb 25, 2020, Task 3 will need to be completed on Mon, Feb 24, while both Tasks 1 and 2 will also need to be completed the prior workday, respectively.

I'd like to be able to program the task schedule so that the task descriptions populate in the sequence as shown while taking into account holidays, as applicable. Note that, depending on the decision date, there may or may not be holidays in the task schedule.

I'm trying to figure out a way to do this, but need some help. Any suggestions?

Alternatively, I'm open to a new approach to design and populate a task calendar with variable decision date that accommodates holidays. Thanks for any help you can provide...

-Stephen