*yawn*
Three 'feel at home' was misleading at the very least. They had always capped the speed abroad to worse-than-2G speeds. Finally the EU action has it seems kicked them into behaving https://jmcomms.com/2017/06/18/sort-it-out-three-using-data-abroad-feels-nothing-like-at-home/
Biting the hand that feeds IT
