Answer:
No. Any letters you write to your frequent flyers are the product of "guidance" issued by either the OCC or the FDIC. They do not set any cap on the number of these communications you might send.
At some point, it might be prudent for you to contact the customers directly and ask if they wish you to continue with your notices. If they say "No," then document the contact and discontinue the practice.
First published on BankersOnline.com 6/3/13