codes giving me a headache

i think the H numbers are more likely batch numbers, or possibly factory identification? the last two numbers are the ones that indicate which is which.

I believe the first letter is the year. G for 2014 and H for 2015. All of the original wave ones that I found were all G, now I'm seeing H. The two middle numbers I believe are a production week. Then the final letter, all I've seen is A. No idea, but maybe factory code.

My DC9 packs are all H37A. Which I would read as 2015, week 37.

Or I could be full of smoke.