I didn't think I was being rude. I have a contract SIM with Orange UK (OVP Virgin -- ring fenced) and they don't include the Republic in my home country definition.

As a matter of fact, I don't have roaming activated on that SIM because I didn't want to pay a 250 quid deposit and I couldn't even use my postpaid SIM in Dublin. Belfast and (London)Derry yes, but I lost coverage once I crossed into IE more than a mile or two.

UK prepaids work in Dublin, but you are paying international roaming. Most carriers offer discounted Irish roaming packages, but you have to affirmatively add them

Stu

PS: If there was anything in my original answer, it might have been that I orginally thought you were a Brit (I didn't read the post carefully the first time around).