They may move to Manchester if they can get slots....
MAN has just slashed its landing fees (12th April) in an effort to attract large slugs of business.
That said you will now be lucky to get a slot, and if you do there is nowhere to park.
Rumour has it that MAN are courting another major low cost carrier for massive expansion.... but unless they can "up" the landing rate and put some more concrete down quick its difficult to see how this could happen !