Err...ther'e no spare VS equipment so would hardly expect them to step in at a moments notice, and what they do have is just too large. As for BD, any displacment of the A330s will be for a medium term thing only; but the biggest thing that counts against them is the complete mix and match of service that they operate and not one standard product.
As for lo-cost operations, then I daresay some nearby airports may be a little bit worried now that this appears to be chosen method of expanding pax numbers quite quickly.
As for BA, one only has to look at how LH somehow operates long-haul out of 3 cities. For crying out loud, even DUS has got a handful of them. This only reinforces how disinterested BA was - i'm sure when just franchise operations were at the regions, the airlines that operated them made profits...but as soon as BA makes an offer too good to refuse to the owners and so buys them, the same routes become unprofitable. If they were clever, they could have anticipated Ryanair and easyJet branching away from London and plonked Go at MAN to get a big foothold in the market.