Speaking as someone who was actually THERE during the entirity of Concorde commercial operations (rather than just an amature outside observer), I can assure you that replacement doors were almost always painted when fitted to the aircraft, and NOT left in the green primer colour. Alpha Charlie was a bit of an exeption in that the door was never painted and THAT is the point being made here. No one is even suggesting a freak of nature for goodness sake, and no matter what you may have read etc, this was regular Concorde engineering practice.
You missed my point completely really, yes some have green primer , some had beige primer on The INNER side, that was the discussion, not the outer side.
The freak of nature was again a point totally missed on you, which is surprising Ricky. So to explain it in simple words, it's highly unlikely that the aircraft in the fleet are today fitted with the said doors they rolled out of the factory with...that was the point, not a about bad engineering practices about painting or anything silly like that.