As I understand matters (and I am no telecoms expert!), it is only Vodafone and EE who are cutting 3g services in 2023.
In the short-mid term, swapping to a O2 or Three sim would be a good solution as both have said they have no immediate plans to retire 3g services.
HTH, Tim

 

You could connect the car to WiFi hotspot on a 4G/5G phone in the car, not sure if it would provide a connection via WiFi when the car ignition is off though.

 

stand down - it looks to be in the US where 3G is getign the chop...

 

We’ve switched off 3G | Vodafone

We've now switched off our 3G network across the UK. Find out how you can get the best possible connection.

www.vodafone.co.uk

Mobile 3G signal to be switched off across North Wales

It's estimated that more than two million people still use third generation only mobile phones, raising fears that North Wales rural communities could be left behind

www.dailypost.co.uk

 

LOL good old google - i don't know why i still trust it....
I supoose when i read it again - its an agrement as to when 3G will be gone not as to when they start turning off...
there is a caveat there for business - i wonder if that would be a work around ( money spinner) for JLR?