@jelloslug to put this into perspective:
Nearest Tesla service to my house is 75 miles away. (150 mile round trip)
Nearest Jaguar service to my house is 7 miles away. (14 mile round trip)
Second nearest Jaguar Dealership is 38 miles away. (76 mile round trip. And actually you drive past it going to the Tesla Service Centre).
So even in the scenario where only one technician is available to service the Jag (which I think is highly doubtful) and he was ill, I would still be less inconvenienced in going to the second Jag dealership.
To be perfectly blunt though, even with Tesla technicians having perfect attendance, and working ridiculous hours, Tesla UK simply can't cope with the workload right now. It's weeks to get a car in even for a 12v battery swap.
So really both Tesla and Jaguar need to invest money into hiring / training EV qualified technicians. However Tesla also need to invest in a vast number more service centres globally, and extend their customer reach outside a radius of their current facilities.
I know Tesla are talking about mobile service as a way to address some of these concerns, but realistically they are only going to be able to fix non HV issues... which is something any non EV qualified Jaguar technician would be able to do too.
FWIW I think outside the US, Tesla's decision to not go down the dealer route, was not the smartest decision.