Star Alliance, can book UA, EVA, SQ, ANA...
As long as you have an open mind, not only look at the flights between US-China - there are A Lot of other options that still work.
Even BA to fly AA or JL would work (limit to Economy because Business costs too many Avios).
Besides both AC and BA have 20 to 30% transfer bonus from Chase and AMEX, at least once a year.
2023 there were 2 times 20% to 30% transfer to AC.
