In one huge auction lot I bought last year was included well over 100 3c imperfs. In general as I've learned more about them, I've learned that there is a lot more that I don't know. It's just a very deep hole - not just plating, but identifying recuts, and now I'm realizing that experimental OB stamps are worth trying to find.
I posted a stamp not long ago that it was suggested might be one. Before sending it in for a cert, I decided to try see if there were any other candidates.
All the stamps in this scan were plated as plate 1 late. The existing candidate is the one on the bottom row with the blue cancel - 3rd from the right.
The only ones that appeared to be XOB candidates to me are on the bottom row, with the ones to the right seeming closest in color to the candidate.
So there you have it. If you would like to express an opinion on any of this, I'd love to hear it. I fully understand that colors online are not accurate. So, take it for what it is worth. I do promise, that eventually there will be a PF cert or two at the end of this and I'll share the results.
The back scan is mostly so you can see the plating marks on back. I have checked none of them yet. Will do so slowly.

