I honestly couldn't tell you whether I have to pay.
I drove into Birmingham recently. All the signs clearly and unambiguously say "charges apply, pay online".
I go online onto their website, and there's no info.
I follow the link to the government website, put in my reg and that says I don't have to pay.
It would be fun if the British government and its equally untalented council prefects could come up with ways of "improving" things or incentivising actions which doesn't involve making any alternative more costly or stress inducing.
I'd call them one trick ponies. But at least the pony has a trick.