I certainly don't think that SEN would be put on the back burner should this take-over come about. Stobart will be very keen to keep growing pax numbers there in order to substantiate some of the optimistic claims that they have made in that regard. The last thing they would want is shareholders getting windy because of a perception that the current flagship operation is suffering as a result of the turnover.
I don't think they would reduce activity at LCY to any great extent but they might well start routes from SEN to EDI and BHD (currently blocked by Flybe) and likely transfer the STN-NQY to SEN, although probably not until 2019.