I have read other posts already, and the UCC for my state, but would like others input on whether the expiration date should be 6 months from the request date or 6 months from the date of the check? (Assuming the check was blank/not dated the expiration would be indefinite until revoked, and that the request is signed...)

My state's UCC the wording is not to clear to me, and I thought the expiration is based on the request date, however if a check is dated 6 months ago or more it is stale dated, so we are trying to determine the best way to handle these.

(b) A stop-payment order is effective for six months, but it lapses after 14 calendar days if the original order was oral and was not confirmed in a record within that period. A stop-payment order may be renewed for additional six-month periods by a record given to the bank within a period during which the stop-payment order is effective.

It is the stop payment order - it has nothing to do when the check was written or dated.