Onion, you are implying that there is some logic to decisions made within the bmi group by your posting and that route decisions are based on rational analysis. This is a rather dangerous assumption. The very decision to launch bmibaby in the first place (kneejerk reaction to easyJet's arrival at East Midlands) indicates that there isn't always any rational reason for their decisions and other basing decisions (opening TeesSide, starting services from LGW) suggest that its network strategy is based on moving aircraft around in an endeavour to find profitable routes.
Until bmibaby make a formal pronouncement, it would be safer to rule nothing out and rule nothing in.