I don't know the answer to your question ( and the markings might not be spaced properly for 116 format anyway... ) but I have two of 1A Autographic Jr.s and really like them a lot. I use paper negatives and sometimes trimmed down sheet film, so always as a "1-shot". Actually, I've got a roll of Acros paper sitting on my desk, looking...

Yes there are markings in the middle, with the typical big circle, littler circle, littler circle, then the frame number.
The circles are centered at exactly 3cm from the top of the roll, which is 3.25cm from bottom of the paper. When you hit the numbers, there are two and they cover the whole distance bewteen: 3cm from top to 3cm from bottom.

Hope that helps and have fun with your autographic. I'd love to see results if you post them somewhere we can see them!

Ned