We currently send a past loan notice on the 7th day and the 15th day. Instead of sending a notice on the 7th day and 15th day we would like to send one on the 10th day to save the cost of sending two notices. Our notes and coupons book say 7th and 15th. Can we do this if we change the notes and coupon books to accurately state 10th day? Are there any regulatory issues that I should be concerned about?

Unless you have it in your contract with the borrower that you will notify them when they are past due (unlikely), or state law requires it, there is no past due notice requirement I can think of off the top of my head, less home ownership counseling notices.