As of 9.20am today (Friday 23 July) there is a headline note on their web page indicating that there are to be further changes on certain routes from Monday, but no details. Their timetable page has no timetable after Sunday (but still shows the "full" timetable applying until mid-September(!) - this should now be taken down as it's never likely to run.
I also tried booking a Manchester to London journey for Monday. The only clue was that, when I tried to book the 10.55 (the via Crewe service, which I assume is to be chopped), there were no Advance tickets available, and when I got to the point of booking a seat, I got a strange error message saying I was not authorised to proceed.
Real Time Trains is still showing the two trains per hour timetable applying.
I appreciate these are fairly short-term alterations, but it seems a pity that, with school holidays starting next week, the information is still not accurate on their website only 3 days before!