wellygary:
Don't worry, BREXIT is going to put a stop to that for you....
Sat 2 Jul 2022
"Roaming charges are back after Brexit – beware high mobile bills
Giffgaff and Tesco have joined EE, Sky Mobile, Three and Vodafone in making contract changes"
But, if you dig a little deeper: (https://www.three.co.uk/go-roam)
If you’re on Pay As You Go, or your Pay Monthly plan started before 1 October 2021, these charges won’t apply. Republic of Ireland and Isle of Man are excluded from the daily charge. Our Fair Use Policies apply in Go Roam destination
So, a 3UK prepay SIM is still a very good solution if you're travelling