Here's some info I found on another site, where someone showed a can
73 = 1973
AP = Ardeer Plant ... which is in the town of Ardeer, Scotland
15 = Day Number
10 = Month Number
So, 1510 is October 15th
S - I don't know the meaning of 'S'
2 - This is usually the shift when it was packaged, ie 2nd Shift