The delays to the exam on that power car was supply chain issues waiting for obsolete parts to be specially manufactured, this is common with older rolling stock which is no longer supported for parts.
Both London Underground and Tyne & Wear Metro have to maintain fleets of the same age and don’t have this same issue with part availability - they saw the issue coming and began making the parts in house. I don’t know about LU, but this practise is certainly still in place on the Tyne & Wear Metro even after Stadler took over maintenance and it remains effective - with the exception of scrapped 4022, all Metrocars moved under their own power in 2021, and almost all of them carried passengers, which is quite an achievement for a fleet of that age
Parts availability doesn’t have to be an issue, it’s only an issue when it isn’t planned for and preventative action isn’t taken, which it appears Laira haven’t.
But is also providing ample time for the fitters to rectify faults like the one on 43239 which is rumoured to have been afflicting the power car for the three months. Granted, it wouldn't help if the power car spent the week at Neville Hill or Craigenitinny because the DfT are choosing not to use them, but that is what fleet controllers are paid to do. As has been said elsewhere, taking 14 months to perform an E exam on a power car highlights the issues. Wonder how long an E exam takes on a GWR power car
The lack of HST work on XC during the week is down to crewing issues caused by the expiry of the rest day working agreement with ASLEF, it wasn’t a DFT decision.
Effectively, Laira have bid for work that they can't deliver - not very clever.
In fact, Laira is the wrong depot for XC HSTs. The nature of the diagrams means that nothing starts or ends its day there, which means one set is tied up as a swap-out set which really leaves only three usable sets at any one time. Once Craigentinny had decided they didn't want them, then either Heaton or Neville Hill (the premier HST depot, of course) would have been much better bets. I'd be willing to bet that Neville Hill wouldn't have taken 14 months for an F exam.
Not only did they bid for work they couldn’t deliver but undercut competition that could deliver too. Northern bid to do the work at Heaton, which would have been a much better option and unlike Laira, Heaton did have the capacity with the Grand Central HSTs having just been withdrawn at the time.
What makes it even more puzzling is that at the time the bids were made both XC and Northern were Arriva companies, so one would have thought it’d have been beneficial for Arriva to keep the work with one of their own companies rather than contracting it out to First.
Neville Hill would have been a non starter as it was full at the time and remains full now, the space vacated by the withdrawal of the EMR HST fleet was almost immediately taken up by 91+Mark 4 sets made homeless from Bounds Green, under near identical circumstances to the XC HSTs leaving Craigentinny (Hitachi not wanting to maintain anything that they didn’t build themselves for any longer than contractually obliged to).
