Scott #1946 "C" Stamp Block Tag Size Variations?

In going through a large quantity of #1946 both new & used I have found a few that appear to have shorter block tag. I say appear to be shorter since the ones I have are based on a block tag that is misregistered. In the image below the right hand stamp is a normally tagged stamp. The middle is a normal size block tag but misregistered and shifted up. The left stamp is an example with the apparent shorter block tag. You can see the gap that would normally land across the perfs is significantly larger. The corners on the block tag are also quite sharp which would indicate it is not from wear. I have not found any shorter block tags centered on a stamp at this point only a few misregistered ones so far. Is anyone aware of more than one block size?

I don't think so.
I believe the wider gap between the tagging blocks on the first stamp is (to use a mid-1800s term), a "straddle-pane" example, where two normal sized tagging blocks were spaced farther apart to account for the pane/sheet margins. The left stamp was in the top or bottom row of a pane.

Thanks John. I was thinking it might be something like that.