
Is the word and or or missing from that sign?
In other words, do one or both conditions need to be satisfied?
Is it ok for for any vehicle - whether it has a permit or not - to be parked there as long as it is 'within the confines of a marked bay'?
I would suggest that Section 69 of The Consumer Rights Act 2015 might be useful.
It says...
69 Contract terms that may have different meanings
(1) If a term in a consumer contract, or a consumer notice, could have different meanings, the meaning that is most favourable to the consumer is to prevail.