NetSuite - Why is my credit memo not calculating tax on an invoice that originally had tax?

If you are on a subscription model basis, the original subscription initiated in 9/2012 so when a credit memo is created, it will use the original tax date of the invoice, thus 9/2012. We both conceptually agreed that this makes sense, especially if there is a tax rate change. We:
1. move Avatax scripts in CM down to the bottom of the list
2. reviewed nexus start dates.
3. Update bundle