Thanks!
Alan McGregor has been in touch to say he's talked to the head of City Development (the department responsible for the integrity of the sea wall) Those guys are about to begin a large survey of the sea wall regarding its function as a sea defence and sand perimeter, and we should try to attach a survey of the sea wall gaps as access points in themselves to that. Then, when they begin repairs and alterations they have to incorporate access needs too.
This department is also responsible for the beach wall blockades over the winter, so in the meantime Alan is trying to ensure they leave gaps for beach access. They have agreed in principle, but sand containment seems to be their only interest, and the construction crew may just put the blocks in the same place in usual, or leave gaps in unhelpful places, in which case we've to report it and get them to change it.