France Sc#76A? What Do You Think?

Well, I have just started to dive into classic France and stumbled upon this one.
(and I am just learning the ins & outs of France, so be gentle)

I have read a few posts on France here (thank you Rod. Perf12 and others), but I am still not sure about this one.

Based on the position of the N under the B, its Scott's Type I
and the Imperf looks good and not trimmed from what I can tell.
So is it a Scott 76a or a French Colony Scott 29?
I haven't read about a valid way to tell. But if there is a way, I am sure you will tell me.
Maybe the cancel has clues that I am not aware of?

Opinions?

Just on the law of averages I'd say it's French Colonies.

#76a only exists mint as far as I know. I believe they went out the back door, perhaps given as gifts, rather than being accidentally sold over the postal counter. So, postal use makes no sense.

Reprints exist in slightly different colors than issued, but this looks good. If we could figure out the cancel, it would help. My first wild guess would be MAYOTTE but I can only find one reading MAYOTTE et DEP.S. If someone has the cancels books, their help would be appreciated.