Hi,
I've just posted another reply to your Facebook posts, copied here...
This is an interesting case and a very difficult one to call. The Traffic Signs Regulations and General Directions 2016 (as amended), Schedule 7, Part 6, para 3 states, “...a person driving a vehicle must not cause it to stop on that marking...”. Technically you weren’t stopped on the marking, but how would an adjudicator interpret this?
As a side issue, there’s a minor design error in the upright sign on the photo you posted. The x-height of “No stopping” should be 50mm and “Mon - Fri” should be 40mm. It looks wrong to me, but probably not substantial enough for the PCN to be cancelled on this alone.