OP, a heads up as regards what is likely to happen next...
They are likely to reject and in their reply labour the point about inconsiderate parking, obstruction etc. etc. They're likely to gloss over the procedural issue because this relates to printed matter, not someone's actions which could be batted away with 'sorry, we've learned, won't happen again'.
This involves docs which are supplied with every removal.
Who in the authority's food chain is going to feel that they're brave enough to concede that one of the council's basic docs is improper?
Alternatively, perhaps their smart play would be to concede, and then do nothing about it. The problem is that 'smart' and 'enforcement authority' don't often go hand-in-hand.
Manage your expectations as regards this stage.
But an adjudicator would not be influenced by the inconvenience caused to the council by having to update its docs and policies and accordingly should find for you.
