Can't add passanger to flexible BAH booking - other ideas? Please can you help with the below edge-case?

Scenario:

We're flying LH with BA in the autumn.

There's a 1/3rd chance I need to cancel due to work commitments, so flexibility is important.

I previously made 3 bookings:
* 2 booked in CW,...
https://www.flyertalk.com/foru....m/british-airways-ex

Booking/flight questions Just booked travel in fall for ATH to HER using United Miles in economy. I’m star alliance gold through the United program. First time flying Aegean.

Luggage allowance seems to be 2 at max 23kg which surprised me given status, thought we’d get...
https://www.flyertalk.com/foru....m/aegean-airlines-mi

WN making significant cuts at ATL - (Speculation) effect on DL? Morning all, today on the WN earnings call they mentioned that they will be making significant capacity reductions at ATL. See:
...
https://www.flyertalk.com/foru....m/delta-air-lines-sk

checked baggage allowance for BE ticket w/ MCE seat selection? I bought my family Rome>JFK (transatlantic) basic economy tickets and then paid extra for Main Cabin Extra seats. Am I allowed to check bags for free now, based on the MCE seats? Or do I still have to pay the $75 fee, based on the original BE...
https://www.flyertalk.com/foru....m/american-airlines-

Agoda pay later price advice Hi apologies if this have already been discussed/answered but my search did not yield the answer I am looking for.

Firstly for context I am UK based and generally use our Halifax Clarity card for oversees travel and travel related bookings as it...
https://www.flyertalk.com/foru....m/online-travel-book