A recent challenge to the ULEZ/LEZ schemes based on the fact that the signage was not compliant with Traffic Signs Regulations and General Directions (TSRGD) 2016 has been upheld. Those are the regulations that specify the required road signage.
See https://www.ulezdisputes.co.uk/ for more information. These might be worth pursuing if you have paid fines for not paying the “charges” demanded by TfL in London.
Roger Lawson (Twitter: https://x.com/Drivers_London )
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