As some of you might know, the customs and immigration does not open at SFO until 7:30 AM. If a plane gets in earlier, they are not allowed to open the door until 7:30.

I found out today that is changing but don't know the details. For example, when will this start and how early will they open? Will they have different summer and winter schedules?

It seems UA has moved some flights up. For example. TPE flight will depart TPE 9:50 and get into SFO at 6:25 in the summer (and 11:30/6:35 in the winter). I guess earlier arrival provides more possibilities to connect on the US side but one has to get up earlier on the other side.