Aye, I was one of them!
Coming from Carnoustie to Glenrothes. The Tay bridge was closed so had to dirvert via Perth. Got too within half a mile of the Bridge of Earn turnoff. Sat there for 3 and a half hours before being able to get off the motorway at bridge of earn. Chaos!
Only took 30mins to get home once we got off the motorway. Bet they are all still sitting there!