US Postage Due Variety (?)

A member of our club obtained a very large amount of cancelled, almost complete sheets of Scott J99 and J100. So, I spent some time browsing to find something of interest. Scott value for these items as used, is very low, so I wasn't looking very hard.

For the $1.00, J100, it was easy to see that there were two distinct overprint styles ... a thick, heavy print, and a lighter overprint.

For the heavy style, I picked out a subtle difference and looked through the rest of his examples. This seemed to only occur in one position, and I grabbed two examples (leaving another, heavily cancelled item, for the other bottom feeders.)





The second specimen has the same broken top feature:



I searched and searched, but could not find this same issue with the lighter overprint variety. However, I found at least two examples of a different style of the broken top, shown in the right-hand stamp below:



Are these known varieties? Any value?

Any idea why there is a thick and thin version of the overprint? It is pretty obvious when put side-by-side.

I'll have to look again for that missing D variety. Thanks for the info.