On the Seaford branch, the 'consulted' reduction in high peak frequency from 3tph to 2tph is going ahead. Whilst capacity isn’t too much of an issue - there will likely still be a few seats at Newhaven Town, in the morning - the reduced frequency becomes a pain when a cancellation is encountered, or when they decide to spin the incoming (to Seaford) service at Newhaven Marine because it's five minutes late, as happened a couple of weeks ago.
The changes also mean there are no longer good connections at Lewes, ex-Seaford, onto peak London Bridge services, which of course is where the majority of London commuter traffic is headed. Our options are a dwell of 20 minutes at Lewes (versus a typical 5 minute connection, today), or to take the Victoria connecting train and change at Wivelsfield, Haywards Heath or East Croydon for London Bridge, which will entail standing for that leg of the journey.
I'm surprised to see the 07.12 Eastbourne-London Bridge (which some may recall was the 2x442 operated service, for a few years) is going, without a similarly timed replacement. The last direct London Bridge train, from Eastbourne, will now be the 06.36 (arr. 08.13), and when this becomes widely known it won't be popular, as the 07.12 is a well-used train and removal from the timetable could lead to crowding on the remaining Victoria services around this time.
One other change I've noted is that peak Victoria trains will call at Cooksbridge or Plumpton, alternately, but not both. Selfishly, I'm happy with this as it will speed my journey marginally, but I think this means fewer peak services for both villages, overall. I expect to see some lobbying, and the 'culled' calls reinstated over future timetables.