Once 'enhancement" I've discovered which I don't ever remember seeing on the old design: "The flight selected has sold out whilst you have been completing your transaction. Sorry, please try another BA flight." happens again and again when trying to make last-minute bookings.

After double checking 'real' availability on Galileo, t'would appear that it's only the return leg that's problematic. So why doesn't this 'new' version of fare explorer offer to A) price the outward journey only; or B) suggest inputting a different return date?

I would be interested to know how much user testing BA does before rolling out these changes to everyone. This glitch could've been caught in a nanosecond and is likely to irritate the hell out of last-minute travellers.