Interesting Franklin 156? Is This A Mustache?

I have other stamps to add. This one was an estate sale album purchase. It seems to be a 156. I would defer to others to help me further identify the stamp. The oddity for me was seeing BF with a mustache. Is this a normal element on these 1C Franklins?
Front

Back

This was my oldest stamp for a bit. Stay tuned for another oldie but goodie.

Any help with confirming this is a 156 and with understanding the mustache is appreciated.
Whisky for my men...