O2

Update on this is that I spoke to Samsung who went on and on about an international SIM card and use it for 24 hours and then will be region unlocked , after 3 attempts at same question they eventually said basically if you have used your phone in co...

I have actually checked my phone and there is no VoLTE option, phone does not have it.

Many thanks, as long as I can make calls and send texts back to UK I am happy enough, data not so much of a concern although would be good to have

Many thanks, data is not so much a concern as must be able to text and make calls back to UK