Thanks martin - we had half a summer of roadworks on the A38 in 2008 (I think) and we used the Norton 10 course instead for the duration (same meeting point) - Sam may already be aware and has made plans, but I'll e-mail him tonight to ensure he's aware.
Riding south down the A38 this morning I saw a sign near the Earl's Croome Garden Centre saying roadworks starting 23 May for 2 days. Parked in the layby nearby were some large contractors vehicles and then going down the bank approaching the Upton turning there was a bloke unloading signs from a truck and dumping them in the verge on the opposite side of the road. I don't know what they're planning to do but I hope it doesn't affect Tuesday's TT.