No idea, but LA's rollout of this (officially today) hasn't been 100% smooth. LA/AS communication hasn't ever been great and I'd expect that this has been low on the LA totem pole.

Your only "guarantee" (i.e., they should stand behind it if miles don't post) is if you fly on a flight # that is shown on the AS website as a permitted flight #. (That isn't to say that JJ won't give you AS miles, but there's no guarantee.)

Eligible flight numbers

1–1343
1400–1943
2000–2943
4000–4943

To ensure flight credit, the two-letter airline code (LA) must precede the flight number (for example, LA XXXX) on your ticket receipt or boarding pass.

Note that this rebranding is simply lipstick. Nothing is changing to the actual airlines, their operating certificates, etc. It will be interesting to see if JJ ever adopts the LA code for flights/ticketing as most of the others have.