It is either a commercial decision or else a "shooting themselves in the foot" decison using oxford grads at Loganair.
If I may explain, Loganair are a feeder airline for other airlines just like coca-cola championship teams provide players for the premiership (or rather nowadays premiership teams get most of their players from abroad, just like the airlines get their pilots, but I digress), therefore Loganair pay relatively low salaries to their pilots as they know they are a steppingstone for pilots.
If they employ oxford grads they know they will move on as an oxford grad ideally wants to spend £60k and fly a jet, not a turbo-prop. Thus do they do this deliberately knowing that they will not stay long and get increments on their salary and various benefits related to length of service (the commercial decision)? Or do they employ Oxford grads expecting them to be career pilots and pay for their TRT only for them to jump ship when a jet job comes along (the shooting yourself in the foot decision)? Either way I don't know why Loganair use Oxford grads as I, after spending £60+k would obviously want a jet job, however would use Logan as a stepping stone to my objective if nothing came up straight away.