Earlier quoted context omitted.
PAYG plans do.
Don't they almost all work on a "goodybag" model now where you top-up £x for the next month of tens of GB of data, hundreds or unlimited minutes, and unlimited texts? Using "real" balance is uncommon in my experience
My father doesn't and so pays PAYG rates when he uses his. Which probably makes sense for him, given his infrequent use pattern.