Loganair (book through http://www.ba.com) are adding extra flights for TT fortnight, from Edinburgh and Glasgow... up to 3 a day, they are saying. I haven't looked at the schedule, but that might mean people could see a day's racing and get home the same day.
They are also scheduling 11 return flights a week from Glasgow, and one a day except Saturday the rest of the time.
I'm ot sure how this will be affected by the takeover by Flybe of BAConnect, whose name is on the planes used for these flights...too convoluted for my tiny brain.