How does the head casting date symbol work?

[UrS4boy]

This is from AAN 015341, which was supposedly built in August 1994



This is from AAN 017849 which was supposedly built between the end of March 95 and the end of May 95.



I can see the year and I can see how the date in the month might be designated but I cannot see what the "3" in the middle and what the hash marks (/, // and ///) mean or point to.

I went out to check my spare engine 009528 (a Nov. 92 build) and there is NO such casting date mark.

Good guesses (with logic back-up) requested. (These should be similar for ABYs and ADUs).

[benntenn67]

I think the marks (/, // and ///) might indicate the circle to read the number from (inner/ outer ring of numbers) maybe

[benntenn67]

I think the marks (/, // and ///) might indicate the circle to read the number from (inner/ outer ring of numbers) maybe

so the 1st pic = 30/6/94 ?
& the 2nd pic = 28/5/95 ?