Yes it was regular from May 1986 to May 1990 (actually going to Glasgow not Edinburgh). The Mk3 Sleeper for Aberdeen was worked with the Inverness Sleeper as far as Perth on the 23.30 off Queen Street and then was attached to a push-pull set for the 01.10 Perth - Aberdeen. There was no return Sleeper working from Aberdeen so it was attached to the 11.05 push-pull off Aberdeen to work back to Queen Street.   It was therefore a five day circuit: Edin - Inv, Inv - Glas, Glas - Aber (and return),