33 vs 27 units should mean more doubled up services, not sure how many are used weekdays? 23 out of 27? Friday seems to be popular work from home day, 17.35 from St Pancras to Nott yesterday was very quiet, didn't need 10 coaches. Looking forward to seeing first 810 on test soon through Kettering whenever that will be.
Agreed, my most recent experience of the 1735 was that it was very lightly loaded for a peak time train. But previous trip on the 1505 and it was full and standing.
Anyhow, the thread linked below from mid-23 has a spreadsheet that indicates 24/27 trains were in use on Monday 26/06/2023 rather than 23.
Attached diagrams for EMR 222 diagrams.
www.railforums.co.uk
With 6 additional 810s, you'd like to think that 5 would be available for service. However, if you assume that any 7 car 222 will be doubled up, then that consumes 3 of the additional 810s, leaving only 2 additional units for 5 -> 10 car (although EMR will get more flexibility about when to provide 10 cars).
The picture below is a Real Time Trains screenshot showing yesterday evening's EMR IC departures from St Pancras.
Of the 15 actual departures between 4 and just after 7.30pm (one was cancelled), it would seem that with the 222s, 4 are 10 car, 3 are 7 car, 8 are 5 car
With the future 810 fleet, it seems plausible that 9 could be 10 car and 6 would still be 5-car.
Although, perusing the threads for LNER, GWR and TPE, it also seem completely possible that availability on the 810s will be worse than planned... in which case the capacity benefit will really will be all about the additional seats on each 5-car.