I know one of their secrets - choosing LBA as their number 1 base. LBA has been crying out for a carrier like this for ages and has been long underserved by charter ops. Phil Meeson realised that people form Leeds area DO NOT want to travel to MAN - they want services on their own doorstep.
Jet2 seem to have raised there prices and still no let up - a damn good business model I'd say. The people of west yorks will actually put their hand in their pockets and pay a touch more to be able to fly from there own airport.
I cant speak for ops at MAN, BLK, NCL, BFS but maybe its just LBA has put them on the map and now theyre growing.
Good on them.