Originally Posted by
Virazuno
The only consideration should be that suggested by GentleGiant. Only a BA-coded flight (i.e. BA marketed, irrespective of operating carrier) would count as 'eligible', for status obtaining/maintaining purposes.
Avios and Tier Points should be identical irrespective of operating or marketing carrier.
Not true; BA operated OR marketed, or IB operated AND marketed, also count.
TPs should be identical, but avios are awarded based on the operating carrier's rules, and there are some nuances (e.g., I-class earns more on BA than on AA).