due to the transit ban at TPE, i will be flying TK. so need to work in extra legs on A3.
Until May 2023, A3 has reduced threshold for qualification. you can move from BLUE to GOLD with 27k (plus 6 A3 flights), the details is as below:-

BLUE to SILVER 9k (plus 2 A3 flights)
SILVER to GOLD 18k (plus 4 A3 flights)

also A3 is easier to renew status (providing u do fly a few A3 flights)

12k (plus 2 A3 flights); or
24k (on any star alliance flights)

based on its easier to qualify initially, so I opted for A3 instead of TK.