Here was our work around at the CU I used to work for. Close the loan at the disclosed rate. Then, signed a "Auto Pay Credit Agreement" (or something of that title), then the system would look for Auto Pays each month.
When the sytem saw the Auto Pay, it would generate a "Auto Pay Credit" into their share draft account. (We used this for Direct Deposit and other "Auto" or "Green" type transactions)
If they stopped auto pay or Direct Deposit, they no longer got the "Credit". No tracking, no ARM agreement, and the customer can see the savings.
I'm only responsible for what I say, not for what you understand.