Free Traffic Legal Advice

This is an off-street car park. The restricted area contravention is standard for parking on double yellows and is probably in the traffic order. 

But a car park needs posted terms and condition - is there a board there? Any instructions with your permit?

I think faded DYLs will not succeed as they are recognisable as such.

You may have an argument for 'legitinate expectation' as you have parked there for years without enforcement. BUT (playing devil's advocate) an adjudicator may well take a dim view of obstructing the doors of an electricity sub-station where rapid access may be required in an emergency.
You are anyway on notice that enforcement is happening.

However, at the NtO stage you may have a case for 'vague location'. The keeper (not necessarily the driver) should be able to readily identify the location from the NtO.
'Croxted Road Estate Outside Car Park' is a more ot less meaningless term (There are no indications of entering an estate at the entrance
  )

And if it is not marked as an estate should code 81 be used?
It should have said something like 'Glazebrook Close, SE21 Outside No. xx)'
The house numbers on Google maps do not match those seen on the bungalows)

Against that you appear actually live next to where the parking took place.

Talking of the NtO, are you the keeper and is your name & address on the V5 correct in every detail?

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