The most recent posts in the LAX FIS thread (posts 222-233) indicate that T4 FIS is up and running during the scheduled arrival time of AA192. That said, it is unclear whether pax are separated between the T4 and TBIT facilities, and if so, how they are separated. Some reports (both in that thread and in others here in the AA forum that I can't seem to find right now) suggest that GE/APC-eligible pax are funneled to T4 while others are sent to TBIT; other reports indicate that only GE/APC-eligible pax *without* checked luggage are funneled to T4; etc. The T4 facility might have opened in stages too, such that both of those accounts were true at different points in time.

Consolidated "Customs and Immigration at LAX" thread

If anyone has any latest reports on how the T4 FIS facility is running these days, please do share!