Thanks to Tesco and Lloyds we are currently racking up a godly number of Avios.

I can see that WT+ upgraded into Club is a pretty good deal (£800 to BOS, £1200 to SIN plus a lot of the miles back... very nice!)

However I am not sure how well this will work for no-status members in practice and I'm hoping you might give me some insight:

• Can you MFU part of an open jaw route (e.g. PAR-SIN-LON) to avoid UK departure taxes? (E.g. Upgrade the LHR-SIN-LHR flights only and not the PAR-LHR leg.)
• Can you find out if a flight has MFU space before booking it? (Preferably online, as you can with continental.com advanced mode, although phone options that don't incur a booking fee are fine.)
• Will BA refund/change flights if you do book and it subsequently turns out that there is actually no MFU availability (say, within an hour of booking).
• Are MFU'd non-status members downgraded first in case of IRROPs/equipment swaps? Or do award tickets get downgraded first?
• If you do get downgraded, is there a good process for re-booking and/or compensation to keep you in Club/cheer you up a bit?

Thanks!