That's why I haven't considered BA. It's a long way to 35k TP and it's still an assumption that both BA and QF will remain in OneWorld.Meanwhile I'm stuck in no man's land! 15k TP (SC) with BA, but no benefit until I hit 35k (lifetime OWE) so just over half way with a couple of years of non-earning thanks to COVID. QF I think I left at about 5k SC and probably will sit there for a long time into the future. I do still have a Lifetime QP membership though, not that it's really worth much currently for me.
I'm still working my way towards LTS and would have passed that mark easily by now if it were not for COVID. My progress to LTG has been delayed by probably at least a few years.