Heads up for anyone else affected...
Just 13 days ago on 13 October, Avanti released their revised Sat 29 October schedule which had Euston-to-Liverpool services taking an hour more than usual and being routed via the West Midlands because of the engineering blockade between Rugby and Stafford.
Today, with three days notice, Avanti have cancelled all but three of their direct trains from Euston: those departing Euston at 06:03, 18:21 and 19:11 are still running. For the return, their only direct trains are now at 05:46, 06:39 and 19:48.
At any other times, you will now need to change en route. Instead of the journey time being an hour longer than normal, it will instead be another half an hour to an hour on top of that.
To cap it all, Avanti's email is still blaming the Rugby-Stafford engineering, even though that was supposed to be factored in when the schedule was released on 13 October.