It's been ~9y since going through LAX international (usually transit internationally through UA hubs). Arriving in Terminal B (TBIT) and will be connecting to Gate 68A for AS flight. My question is once clear immigration, can bags get dropped in TBIT or do they need to be schlepped all the way to Term 4? Stated otherwise, does AS have a presence in TBIT?

The sole reason is that I want to hit the lounges in TBIT, and I don't want to have to return there and again walk back to Term 4. I did that earlier this month on a domestic tix, and I had to run just to make my flight. If it matters, flying in C/F on LA.