FlightDetective

I did the opposite - I moved to Ireland for "a year" and 16 years later I'm still here.

Without a doubt, stick with BA. Two reasons - a) you have 13,000 lifetime tier points and as others have pointed out, in four years you'll either have or almost have lifetime Gold. I'd stay for that alone! But also because... b) Redeeming BA Avios for Qantas domestic flights for leisure in business class is a fantastic use of Avios as J class fares on Qantas within Australia are extortionately expensive.

I would also recommend opening a Qantas Frequent Flyer account just to accrue points from credit card spend, bills and all the other stuff, but credit your flights and gain your status with BA.

That's my take anyway!
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