I can also confirm that the issue is fully resolved, so very pleased indeed.... whether the data feed or ExpertFlyer was the issue, my subscription is now wholly justified again...

I managed to apply my GUF2 yesterday to the original W seats that I mentioned in my OP.

However this leads me onto a more GUF related question. Have tried to search for this info, but doesn't seem to be that obvious in the GUF thread/s I found. So looking for some Flyertalk expert help please. I understood that you could combine an Avios redemption and GUF together or AMEX 2-4-1 etc....etc..... As a result of this I assumed that if I can secure the I class seats I needed (with my GUF2), then if AVIOS availability was there for F ( which it was at the point I applied the GUF2 voucher yesterday, albeit currently only on the return sector of my trip) then I'd be able to get into F based on Avios availability.

I had an agent who hadn't applied a GUF2 before, so this all took a while (including a rather punchy quote on tax/carrier charge supplement @ approx £120 each will be double checking this with BA when I can, but took it to just secure the CW seats for now). She did have to seek some guidance about process for all this & the whole call took about an hour (not that I've much else to do on a COVID lockdown Saturday morning) so was very patient. (It all had to be applied manually apparently too) But she advised that as there were no Avios seats in J, then I couldn't subsequently ask for the one way F seats (AUH-LHR only). I didn't think it sounded right, however let it go & figured I'd call back & try to move into F using Avios later in the day. Of course when I checked last night those F seats are now no longer available & using the seat map on ExpertFlyer, I can see that someone else bagged them.

Anyone know whether the agent was correct with her statement? Or where I might be able to get to with this as a complaint/process issue? Which ultimately has lost me 2 seats in F on our return. Plan was I'd also be able to get the outbound if released.

To compound things, this was all a BA holidays booking & therefore only a deposit has been paid at the moment, but the balance on the overall holiday price has now jumped by nearly £1200, so clearly been an error when making the manual application of the GUF, so definitely have to call back in to get this resolved.