Different Sizes Of 1926 Series???

I am noticing that some of the 11c, 14c, etc., that I have from 1926 11x10.5 series are taller. This occurs when there is a large white margin (at the bottom on my examples), before the perfs. At first I thought they were just badly centered, but I held a few up against a normal stamp and they are definitely taller -- not the design, but the actual paper.

Am I going crazy? Or does some super-specialized catalog list these separately because they are maybe from the bottom row of the sheet, or something?

I'm just curious -- these are Bureau precancels (which weren't made using the 1922 stamps), so I am only keeping one of each anyway and not concerned about value etc., but I just noticed that the stamps are actually taller.

Thanks.

I'm not qualified to answer that. I seem to recall someone here used a "Lucy" avatar from the comic strip "Peanuts". The doctor is around here somewhere :)

As far as the stamps go, I would expect to find an infinite variety of paper sizes on all of stamps from this era ... flat plate or rotary press printings. It's the nature of the perforating machinery. Naturally, jumbo margins are preferred.

Cheers!

Brian