For your OOPLA appeal, you put the operator to strict proof that they have a valid contract flowing from the landowner to operate and issue PCNs in their own name at the property.
What exactly does your AST/ lease say about parking? What it doesn’t say is equally important. For example, is there any mention of a requirement to display a permit when parking in your demised parking space?
Can you ask your landlord for a copy of their head lease? If there is nothing in your lease about requiring permits to be displayed, you can say that you only displayed one out of courtesy, not obligation.
Unfortunately, POPLA assessors can be quite moronic at times and will often reason that just because there are some signs in place, the operator must have landowner permission to operate. Thankfully, if this went to litigation, that kind of idiotic reasoning is not accepted and, as in the majority of residential private parking cases, the operator cannot evidence that their contract with the landowner or their managing agent is supreme to the leaseholders rights.