Jet2 would find it easy to get route support, e.g. lapland flights/their flights to Jeddah this winter just gone, don't think that would be to much of an issue, clearly something they haven't yet tried...
SFB could be operated, yes with a one stop, however, flyglobespan dropping out of BFS, could be a perfect opportunity for EMA-BFS-SFB-BFS-EMA with no flight to Sanford from EMA anymore, YYZ would work, but JFK was just pure example, I have to say, it wouldn't work unless it was on a regular basis.