I agree the markings look almost non-existent, but the sign for the bay is just behind your car. No bay markings means you're not obliged to seek out the sign for the bay, of course. No harm in submitting an informal challenge based on no bay markings, but don't expect them to roll over and cancel. You have the right in law to take the matter all the way to adjudication, but the full PCN is in play at the adjudicators.