Although I am a GE user I remember pre-Covid at Liverpool St the WA was horrific for delays because of the 2tph Cambridge, the 2tph Hertford East, the 4tph Stansteds, and the Stratford Bishops Stortford clogging up the two track line, it was too full. I agree it should not return, instead 10 car 720s should be used instead of 745s. If they use 745s they should stick them to the fast that does not call at Harlow or Tottenham Hale (or remove the Hale call) and run them non-stop to Stortford.
Anyway this is way off topic for the 755s. Is there any plan to put 755s on GE diagrams in future timetables or is it just one Norwich IC diagram? If they are testing 4 3 3 and 4 4 3 multiples they must have some plan. Just asking.