Qualification absence plan rules going back 68 weeks in time on a Calendar Year plan

Summary:

Hello

Hope you are well.

We have a requirement where my company is requesting that we prepare a validation formula which will allow employees to book a particular absence type from the date of childbirth which is stored in the maternity absence record.

The issue we have is that the plan is based on Calendar Year, and we want to allow employees to book this particular leave up to 68 weeks from Childbirth Date.

Is this possible to do via fast formula?

Thanks for your help