Also worth noting that a plane no bigger than a twin prop has landed at Corvera so at some point an airline will have to test the airport with a passenger plane.
From what i can see, LBA is on a B733 (148 seats) and MAN is on a B738 (189 seats). A 3k m runway would be more than sufficient for takeoff/landing.
with only the 2 routes being on sale for now i would imagine (like others have suggested) they're dipping their toe in the water. If things go well, we may yet see the re-introduction of NCL/EDI, maybe even more?
Still think it's a totally bonkers airport so for now, well done to Jet2 for commiting but don't be surprised if things don't work out like MJV did