sdr thank you for the correction. Yes you do want a full lien release on the note which I thought is what I implied but didn’t elaborate clearly enough. Your point being made that the note being the important instrument is what is important here.
I am not sure what you have seen but I have not been involved where the approval letter is not specific or accompanied by an indication of the specific instructions of the intention of the lender. That is, in the best case where they authorize a full lien release (of the note) or they forgive the note. Other times I have seen notification of an approval (lien release) based on the homeowner agreeing to a conversion of the note from a note secured by real property to an unsecured note.
The point is that when the approval letter does get issued, it usually is pretty easy to figure out the intention of the lender is.