Where did you hear this from?
I think any expansion plans for Luton from Monarch will be on hold for a year or two. The airline needs to source atleast 5-6 additional aircraft, just to cover the additional expansion from East Midlands, Leeds-Bradford and Birmingham...
At present the airline is wet leasing 737's from some European carriers, to cover this expansion. But doing this, is expensive and cannot fully carrry through Monarch's brand, so I am sure they will want to get their own metal and crew flying these routes first.
I hope not, but in the short term, it wouldn't surprise me if an aircraft was trimmed from the Luton base and the schedule tweaked to operate from one of the new bases and doing something similar from LGW and MAN.
I didn't. Was just a hunch considering they've recently opened routes to Rome and Munich. Fair points though, didn't think of that.