If you are having the borrower sign a new promissory note then it meets the "refinance" definition in Regulation Z. In these cases, they should basically be treated like any other refinance and follow all of the applicable regulations. If you were to modify or do a change in terms of your existing note prior to it's maturity then it would not be considered a refinance (generally, although depending on what ou are modifying it could cause it to be a refi) and you wouldn't have to give all of the "normal" disclosures.
How long until retirement??