There doesn't appear to be any seats available on flights to/from Birmingham from 6th-8th May and 2 x return rail tickets are £287 - the journey home is 6.25 hrs - so its a 'no' from us I'm afraid.
Shame.
Jeez can fly for much cheaper than that from down south. Rail out of Edinburgh on a sunday has always been bonkers. Current cheap rail from the south is Lumo but not sure how often it stops before Newcastle.