I think there is, perhaps, an opportunity for Regional to work with the new slots for EDI and ABZ to LHR under the VS banner, they will need to lease some larger equipment in the short-term, though.
That, or constructing a deal with IAG that is similar to Sun-Air, basically franchise model.
A third, extremely slim possibility, is that Regional would be integrated with city flyer, somehow. I don't think the ERJ 135/145s would remain for long, but cityFlyer has a number of ERJ-190 options it could exercise, if so desired.