There are several very strong points you can rely on if this matter ever proceeds to the small claims track of the county court (The ultimate dispute resolution service). However, since the time for any appeal has passed, these arguments will be useful to challenge the operator’s claim in court.
Ambiguity in Terms:
The sign specifies "Commercial Vehicles ONLY," but the bay markings say "Vans only." This creates a clear contradiction and confusion about what is permitted. Your vehicle is registered to your bakery business and is used for commercial purposes (evidenced by being loaded with sacks of flour). This aligns with the sign’s stated purpose but highlights a lack of clarity in the contract formed by the signage.
Unclear Definition of "Commercial Vehicle":
The sign does not define what constitutes a "commercial vehicle." UKPS has attempted to retroactively impose requirements such as DVLA or HMRC classification, but these criteria are not stated anywhere on the sign. This ambiguity works against them, as the terms of any contract must be clearly communicated to the driver.
Purpose of Parking:
The vehicle was being used for a commercial activity (loading supplies for your bakery), which qualify it as a "commercial vehicle" under any reasonable interpretation.
Inconsistency in UKPS’ Approach:
When challenged, UKPS argued that your vehicle isn’t registered with the DVLA as a commercial vehicle. You correctly pointed out that neither of your box vans (clearly commercial vehicles) are classified as such in their logbooks. UKPS then shifted to HMRC classification, further demonstrating inconsistency and a lack of defined criteria.
Proportionality and Reasonableness:
The £100 charge is disproportionate in light of the circumstances. Your vehicle was parked in line with the apparent intent of the signage (for commercial vehicles), and there is no evidence of obstruction or misuse.
These points collectively highlight the weaknesses in UKPS’ case. The contradictory terms, lack of definition, and reliance on post-facto reasoning undermine their ability to enforce the charge.
In the meantime, you can safely ignore any debt recovery letters. The debt collectors are powerless to do anything, no matter how threatening they sound. Ignore them.
IF UKPS are sufficiently intellectually malnourished to try and make debt claim in the county court, come back and we will assist in easily defending any claim. We do not need to know about the debt collector letters. If you receive a Letter of Claim (LoC), which will give you 30 days to pay, not 14 as per the debt collectors, show us and we can assist in a response.
Perhaps you should seek out a better wholesaler to spend your money with, especially one that doesn't really care that their genuine clients are saddled with spurious invoices for £100 a pop from their contracted parking operator.