I have put together a customer contact database in Filemaker and need to incorporate a weekly report of dates to visit customers each week. I

One way would be to have two fields: next scheduled date and increment. Next scheduled date would be an auto-enter calculation (which could be overwritten) such that if the current date > next scheduled date, the next scheduled date gets recalculated by adding the increment to it. Use Evaluate so as to trigger the calculation.

That's nice and neat and great for where the intervals are regular, but the increment between Tuesday and Friday and Friday and Tuesday aren't regular. How do I cope with that using the same data input fields as for regular increments?