As a resident who uses line at times, and can see line from my house, it does vary day to day, and different times of day, possibly not getting worse overall, but 2car sets are much more common on Portsmouth-Cardiff than under the old timetable until May.
We are not talking about occasional short 2car trains, now happens many times every week, so no longer exceptional.
I suspect that it is still at 0% for managing a full days timetabled service without any short forms or cancellations in the 6 months since timetable changed, unless anyone can find a day where everything ran fully.
Today looks like 1F03, 1F12, 1F19, 1F28 are just a 2car 158.
1F12 has managed to lose 41 minutes so far, it will struggle to meet start time of return from Cardiff, unless they can reverse and clean it in a minute or two
Real-time train running information for 1F12 0923 departure from Portsmouth Harbour to Cardiff Central on 17/11/2023. From Realtime Trains, an independent source of train running info for Great Britain.
www.realtimetrains.co.uk