I assume you are aware that not so long ago, batch after batch of new London buses were delayed for iBus fittings? It still wouldn't surprise me if electrification delays were assisting with hiding any issues with supplies there as well. Had you also considered that by virtue of being the largest single customer by far with long-term procurement agreements, that TfL may be coming at the top of the tree to the detriment of everyone else?
I think, once you remove the dripping sarcasm, what you're showing here is that you have very little understanding as to how large-scale procurement works. I'm no expert either (there are certainly those here who have more experience than I do), but I do know how long it takes, for example, the landlord of my building to procure and contract services (it's a two-stage process for every contract under Section 20... in theory they have to do that every time a single item comes to more than £250, but largely work on framework contracts in the millions). It can take over a year between first notice and agreement.
As for other industries, may I suggest you look at the energy sector? Or large-scale public works? South-East Water says hello.
This is a deadline that was plucked out of thin air by Whitehall, with little to no idea of what would actually be required to make it happen.
