Used half a litre of oil in 60 miles. There is now white smoke from the exhaust and signs of mayo forming in the oil cap, no bubbling in the expansion tank this time but it looks like the head gasket has gone again and that either the head is probably warped or uneven in some way.
Operation Manchester, which was a planned trip to display the car as part of a stand at the Footman James Car Show in Manchester in September, is now officially off. It was intended to be the last real mileage this car does on it's current engine and a goal for me to work towards but there is limited space and given the high chance that my car wouldn't survive the 400 mile trip, even if it was working now, it'd be unfair to compromise the stand.
Still hope to make Grantown-on-Spey if I can bodge it in some way.