In reply to dgp:
https://www.bbc.co.uk/news/uk-wales-46045759
The Welsh Government Planning Inspectorate have overturned Anglesey Council's planning objections (primarily that charging at Elin's Tower and South Stack carparks would cause congestion on the approach road due to people parking roadside instead).
This gives the RSPB the go-ahead to install meters at the carparks, so people will have to pay either the £5 charge (or a reduced charging rate for locals) or else join the RSPB (£48 annual single membership; members park free).
It also means Anglesey Council will have to pay the RSPBs costs for the appeal.
(I don't think the parking / turning areas further up the hill are RSPB owned, so early-bird climbers may still avoid the charge?)
Post edited at 20:42