Evening Graham
I think you may be right about Lexus Nottingham, although at least they didn't lose all of my music on the hard drive thank goodness!
The technician who allegedly tried to update my car had gone home by the time I arrived to collected the car and the service reception team didn't know what had been done, which in itself was disappointing, especially as I'd told them of the problem when I booked the service and informed them that another customer had been to Lexus Leicester and they had fixed the issue.
Anyway, I eventually got an email from them which said "they had done the update but it didn't work". They went on to say "they had spoken to Lexus technical who had advised they would have to wait until another fix was out". They unhelpfully said that Lexus "could not put a timescale on when another fix would be out" so they've simply told me they'll be in touch if / when they receive something.
Frankly I feel as though I've been fobbed off, which is irritating.
I note you say that Lexus Cardiff clearly have the answer, but going to them would cost me a lot in terms of time and money. I might give Nottingham a ring though and ask them to talk to either Leicester or Cardiff and find out what they need to know, get it from Lexus and then update my car.
Thanks for the information.