My production date of 26/12 was brought forward after I requested some options to be cancelled!
My guess is that your vehicle, then, fitted a manufacturing "profile" that was being made earlier; particularly if you switched something like 7-seats to 6-seats, or from coils-to-air as early on the other models were "delayed". Tesla definitely has problems with supply-chain (hence their on-going expansion of in-house built components)
My suspicion is that UK staff know little about production scheduling because the factory doesn't either. i.e. Factory juggling production for other reasons - supply chain maybe, the Boss needing great Q4 results, so priority given to locally-deliverable vehicles so more sales closed before 31-Dec etc.
Can't believe the incompetence with regard to deliveries
To my mind this relates to new models (i.e. it has historically been the same). Problems are found (either in production, or on shipped vehicles) and production is then adjusted, with delays. The rate at which Tesla has ramped-up production of MX has been slow (compared to, say, the new GM Bolt EV) Lack of experience in that area, lack of cash to fix issues post-delivery, production started before all issues solved, or just the desire to pay as much attention to detail to possible. Annoying for you and I think it very important that Tesla fix that (with the upcoming launch of M3),
Doesn't make it right of course, and I don't know how a car company solves that - short of being "huge" and having much more experience of new model shipping. Huge-company has more sway with suppliers than small-company of course, so supply-chain may be another problem, along with the very high levels of innovation - Falcon-wings may well have still been a problem at launch, 7-seats + Coils definitely turned out to be ...
The up-side, FWIW, is that later-shipped models will be more sorted.
after 6 months I received a one word valuation which not surprisingly was £6K lower
I didn't trade anything in but from what I read the trade-in valuations don't really exist until the delivery date is firm.
Hopefully the Reps get uncomfortable with all the flack they receive and that improves the process upstream. Again, no consolation for you though