Was it too complicated to go 701 (because no one starts a count with 0) (TL), 702 (SWT), and 703 (GN) for the Desiro City and 711 (LO) for the Aventra ? They shouldn't be surprised if they quickly come to the end of the 7 series, unless they start stacking some in the middle of 700, 707, 710, and 717, which would be even less logical !
Quite. Though it's fine to start with "0" as the Super Express Trains are showing- CLass 800 for the main batch of Bi Mode, 801 for the EMUs, 802 for the "Plymouth & Penzance" bi modes. Possibly 803 for the TPE lot?
the 7xx series is quickly becoming as much of a mess as the Electrostar numbering:
357: AC Only LTS fleet
375: mix of DC and dual voltage, mix of 3 & 4 car, at SouthEastern
376: metro style fleet for SouthEastern
377: mix of DC and dual voltage, 3, 4 and 5 car, with some fairly major technical variations
378: metro style fleet for London Overground, some dual voltage
379: AC only Stansted Express/West Anglia
387: 110mph Electrostar version 1.5
And of course in the 37x range:
370: Advanced Passenger Train
371: unbuilt "Universal Networker" intended for Thameslink 2000
373: TGV Trans Manche Super Train - the original Eurostars
374: Siemens Velaro e320 - the new Eurostars
Numbering is a mess. I'd have hoped the 7xx range, like the 8xx range, could be tidier. Oh well.