They sometimes do a blitz to target lots of contraventions.
This is what the legislation says about code 27. In your case it could also apply to cycles I guess.
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Prohibition of parking at dropped footways etc.
(1)In a special enforcement area a vehicle must not be parked on the carriageway adjacent to a footway, cycle track or verge where—
(a)the footway, cycle track or verge has been lowered to meet the level of the carriageway for the purpose of—
(i)assisting pedestrians crossing the carriageway,
(ii)assisting cyclists entering or leaving the carriageway, or
(iii)assisting vehicles entering or leaving the carriageway across the footway, cycle track or verge