I think you have an argument to make around the signage. Looking at this council photo:
(https://i.imgur.com/3yOSYcN.jpg)
it is clear you were parked here https://maps.app.goo.gl/jyoVSdfFpDPeTaXT6 opposite the garage with the white doors:
The CEO took a photo of this sign:
(https://i.imgur.com/yPVv6U2.jpg)
I'm not sure if it's the same sign but the nearest one I would find is here: https://maps.app.goo.gl/54ib63LHbBYQabk88
Assuming that's the nearest sign, it would be over 45 yards from your car:
(https://i.imgur.com/jP9gtHT.png)
Incandescent has identified some other signs, but signs that are either on the other side of the road or completely out of sight don't count. The Traffic Signs Manual at chapter 3 says:
13.4.15. A sign should normally be erected within 15 m of the start and end of the prohibition
15 metres is 16.4 yards, and in this case the only sign on that side of the road is over 80 yards from the start of the prohibition (which starts at the junction with Dunstable Road.
However before going all-in on this argument, are you able to go back and check if the signage situation has changed at all since the google car last went round? We don't need any photos, we just need you to tell us if the signs visible on google street view in 2019 are still the only signs there.
I've also requested the traffic regulation order for this location.