I've never seen anything like that. Here on CT, I've learned that with incuse lettering, what looks like MD is actually DD, and vice versa. Just the opposite of raised lettering.
the letters do look the same but did the same thing happen to the windows also. they look like they are seperate
If the doubled design is incuse (which it appears to be), it is a form of machine doubling even if there is what looks like notching. Confusing, I know.
Its still cool to look at! I found one like that and posted it about a month ago. I saved it just in case one day, maybe, just maybe, they would ever change their classification. Always hopeful