I also think over last 5 years or so it's often not been the very top SG1 referees who have done the Championship semis, presumably in part because they have been used for some of the key Premier League games near the end of the season. There's plenty of those (plus FA Cup final of course) next weekend.
I think the semis might go to likes of Gillett/Jones/Bankes/Friend.
I wouldnt be surprised to see Hooper/Scott/Harrington/Salisbury involved with Oliver or Marriner getting the final if Moss isnt given the big send off.