These files show the redacted notice.
The route in - which does have signage. But only on the way in - this was the evening before when it was dark and the signage is to your left on the wall. There is a much smaller sign a little further ahead on a metal pole.
The other photos show the route out of the car park. I turned out and spotted a workmate - stopped for seconds on the double yellows - and they jumped in. There isn't any readable signage when you turn out of the car park (where I stopped). A bit further ahead there is a very small sign on a metal pole but this wasn't in vision where I stopped (very briefly!).
https://imgpile.com/p/OSg97lp