There are no signs for dropped/raised footway crossings but you often see dropped kerbs at the corner of roads and obviously some have tactile paving.
But we have seen these entire junction tables upheld as a big pedestrian crossing area at the tribunal.
I would go on with this not least because their rejection is daft although we don't know what your challenge was. We don't know why the PCN was issued (see law below).
Are you the registered keeper and has the logbook gor the correct name and address.
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The law
86 Prohibition of parking at dropped footways etc.
(1)In a special enforcement area a vehicle must not be parked on the carriageway adjacent to a footway, cycle track or verge where—
(a)the footway, cycle track or verge has been lowered to meet the level of the carriageway for the purpose of—
(i)assisting pedestrians crossing the carriageway,
(ii)assisting cyclists entering or leaving the carriageway, or
(iii)assisting vehicles entering or leaving the carriageway across the footway, cycle track or verge; or
(b)the carriageway has, for a purpose within paragraph (a)(i) to (iii), been raised to meet the level of the footway, cycle track or verge.
This is subject to the following exceptions.
(2)The first exception is where the vehicle is parked wholly within a designated parking place or any other part of the carriageway where parking is specifically authorised.
A “designated parking place” means a parking place designated by order under section 6, 9, 32(1)(b) or 45 of the Road Traffic Regulation Act 1984 (c. 27).
(3)The second exception is where the vehicle is parked outside residential premises by or with the consent (but not consent given for reward) of the occupier of the premises.
This exception does not apply in the case of a shared driveway.