Map-In Requirement to Send Notice of SFH+Fed Asst?

I've operated under the knowledge (assumption?) that the "Notice of Special Flood Hazards and Availability of Federal Disaster Relief Assistance" should not only be delivered when a MIRE event occurs, but also when a low-to-high risk map change occurs and the lender becomes aware of the change (chiefly related to LOL monitoring notifications).

I've found numerous threads where folks have asked about this requirement and found that it is commonly held by the experts posting in this forum that the notice should go out once the lender becomes aware of a map change, but... I've been digging around all day and cannot find a single reference to this notice being required outside of a MIRE event (FDIC, OCC rule books; Federal Register; NFIRA, FDPA, etc.

I think I'm cross-eyed at this point and hoped that someone here could point to where the requirement to send the Notice for map-in's is stated in law or rules (or regulators' commentary, for that matter)?

Thanks in advance for any/all assistance!

Question 57:

https://www.bankersonline.com/sites/default/files/tools/flood_faq_2011_10_17.pdf

Although Q 57 is not finalized, it is a best practice that the regulators are enforcing.

Appreciate you, Randy! I realize now I wasn't looking at a document that included the 2011 updates.