The short answer is beats the hell out of me. The longer answer is that, other than filing for approval as a totally new product and starting from scratch, there are/were three pathways for keeping an existing product on the market:
(1) Grandfathering. There is a separate database for that, but it clearly does not include lots of things that “we all know” were on the market at whatever date in 2007 was relevant, haven’t changed manufacturer, nor recipes that anyone has been able to discern. I know others who have tried to search this database and come to the same “wtf’ conclusion. It MAY be that the database was a snapshot at a particular time and just isn’t up-to date. A lot of C& D and Pease blends are on this database If you search under Laudisi. I have not looked for Sutliff or Lane. And my understanding is that you can still submit an application for grandfathering. And Kretek got Bracken Flake grandfathered. Huh?
(2) Substantially Equivalent to something that has been, or I guess could be, grandfathered. Last I heard, the FDA hadn’t published a database for these applications, in part because the industry raised trade secret issues. There is a “batch application“ procedure the FDA has opened for this route, and that, combined with the (for now) confidentiality might be the preferred route for some companies who are paranoid about disclosure, but I don’t know.
(3) PMTA, which appears to be the route companies like D&R , Intercontinental and other players in the convenience store “pipe tobacco” market have followed.
From what I have heard, a lot of the paperwork the FDA wants to see is focused on how you market the product. They really want to corral vapes, alternative nicotine delivery products, and anything with youth oriented flavors, and I hear those products are getting the full proctologist examination, with less concern about chemistry than one might have thought early on. One Lane executive on this very forum a few years ago said products had to be “molecule for molecule“ the same, an interpretation that had already been superseded by informal guidance, but was still the prevailing view in the trenches of the trade.
So my best answer is, still, beats hell out of me. And nobody is paying me to come up with a better answer. Besides which, I am fully, completely and happily retired, and therefore I can’t legally take a fee anyway.
ETA: Several pages worth of blends by Lane , Sutliff, and Laudisi were submitted for grandfathering here.