My analogy for all this would be that you were doing 32 in a 30 zone then being told they'd changed the limit to 20 later that day (effectively as happened with UEFA and their changing of the FFP toolkit) but effective at 8am. But as you weren't to know, they'll let you off with a £50 fine.
Then, a few years later, you get a summons for the same offence saying that they'd checked their equipment, which turned out to be faulty. They're not 100% sure but think you were doing closer to 40 so they're taking you to court for dangerous driving.
I’m not going to claim to know more about this than you PB and have appreciated reading about it all from what you’ve written, but is it not more like:
Caught doing 32 in a 30, authority retrospectively changed to a 20 and so said you were wildly speeding. Agreed with authorities to “take a pinch” and a fine and not to question the fact that they changed their own rules after the event to maintain good relations.
Then years later get accused of stealing the fuel in said car you were speeding in and hence shouldnt have been able to go that fast in the first place.
We’re now appealing that to say we earned that fuel fair and square.