Weekends all services can be 345s. Monday to Friday the 345s are targeted at the heaviest loading peak services, to help reduce dwell times and improve punctuality. That means they aren’t always in the right place to work all the off peak services, as the platform working at both Livetpool St and Shenfield dictates what forms what.
Indeed this - although the timetable itself generally remained untouched at the December timetable change, it was mostly to do with changing around what train during the PM peak was a 315 and what was a 345.
On the old timetable, majority of the 345s had been booked to do trains leaving London Liverpool Street after the 1800 departure I think it was however many customers complained that too many of the departures, particularly during the summer where they wanted a train with AC, were 315s between 1700 and 1800 (of the 15 departures during this time I think only 3 trains were 345s or something like that?). Now especially after 1730 a lot more trains have been converted to 345 operation however this has meant other trains outside of these times have been reverted back to 315 operation.
As someone who enjoys class 315s this is obviously welcome news as a lot of the trains I get have converted back from 345s to 315s! (Yay
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