Some QR/BA mixed booking questions
1) If only QR publishes a cheap fare between two cities, does that mean it can only be booked via QR (or a TA) and not via BA? (ba.com returns "We’re sorry but we can’t find any flights matching your search".)
2) Is there any way to book a mixed QR and BA booking in a way that would allow UuA on the BA metal/flight numbers?
3) Assuming the answer to 2) is no, it seems even booking via QR's website allows to fly on BA metal or on QR metal with BA flight numbers. I assume flying on a BA number is better for a BA Gold in miles terms? Are there any downsides to doing so?
TIA!