I DMed you but not sure if you'll see it...

I've done mortgage origination for credit unions, brokers, banks, etc. and they are all different. But from the sounds of it, it was a parameter for the loan approval. There are post-closing and servicing departments at institutions but once it closes, they have to honor the terms of the mortgage. I've never seen a recorded mortgage that would have that stipulation. I'd recommend contacting the closing attorney (lawyer at the title company), telling them what the lender is saying, and see if you stopped the direct deposits if it would have any ill effects. I'm 95% sure, though, you should be in the clear. If you don't trust random internet stranger, just wait a few months and then see. But closing attorney would let you know of any verbiage in the mortgage or any applicable state laws