Looking at the St Pancras departures, I would guess that combined 4 units across 222 and 810 fleets have stopped playing. Earlier today, it showed units allocated to all services, running with 4x 10-car departures in the peak, which means 23-ish sets in service. At the time of writing RTT is now showing that only one will be, but there is also have a gap with no unit allocated to the 1832 Sheffield, and just about running everything 5 car takes about 19.
This does seem to be a rather typical day in that just about enough get sent out in the morning, but come the evening peak the fleet short-forms are inevitable and cancellations pretty common. That is normal. However, still getting days with absolutely shambolic performance (e.g. Thursday 2nd and Saturday 4th).
This thread will be a year old next week, no sign that Hitachi have really got a handle on things. Which must be pretty embarrassing, if you are a Hitachi manager.
They certainly used to make use of Central Rivers. Not sure when that stopped but I believe it's when Hitachi took over the maintenance, so it's definitely been a few years
This would be the operationally obvious thing to do, provided they have the capacity to do the work (I assume they do as at least a few ex-XC units are in storage).
However, what is probably happening is some Commercial Director that's a long way from the front line is looking at the contract performance on the 810 job, which must be absolutely dire, and is refusing further spend on getting Alstom to get 222s into shape.