It’s similar on GN.
The notable flows are things like Stevenage to Hatfield, Hitchin to Welwyn, Welwyn to London, Hatfield to Finsbury Park.
The Horsham to Peterborough service remains quite busy (in comparative terms!) which makes this a bit of a bad choice for a service cut - the string of new towns north of Hitchin provide a completely different dynamic to the Cambridge branch (which has been largely dead off-peak since March).
The observations from others about Cambridge to Kings Lynn are interesting, not my neck of the woods so not something I’ve really seen. I’d agree that my observations would support the notion that these people are generally not travelling south of Cambridge.
The Thameslink/GN timetables for next week are on their website, and will be reflected in online planners from tomorrow. I've had a quick look from a Stevenage perspective:
On weekdays I expected the additional peak trains to go and for the 15 minute all day interval Thameslink service to remain, but no! The peak extras are retained (hopefully still 365 operated) with one of the Thameslink services removed (a Peterborough - Horsham)
This means places like Huntington, only have an hourly service throughout the day supplemented by the peak extras
Arlesey and Sandy don't get the peak extras so an hourly service only
After 20:00 the two 'fast' trains from Stevenage to London an hour are 15 minutes (xx17 and xx32) leaving a 45 minute gap
Semi fasts (i.e. the trains that call at Knebworth, Welwyn North, WGC, Hatfield, Potters Bar) remain at 30 minute intervals
The inner suburban services via Hertford appear unchanged at 30 minute intervals
On Saturdays the 15 minute all day Thameslink interval is retained so there is a better service on Saturdays than on weekdays, significant at places like Huntingdon and Arlesey
Semi fasts remain at 30 minute intervals
Inner suburban via Hertford unchanged at 30 minute intervals
On Sundays there are two 'fast' trains an hour (unchanged) one to Kings Cross and one through the core
Semi fasts reduced to hourly
Inner suburban via Hertford unchanged at 30 minute intervals