Having issues with Cull.

I have noticed a potential issue with the Cull item. The amount of CS I have acquired does not coincide with the remaining stacks on Cull. (i.e. I have 74 cs and 28 stacks remaining) In this particular game, when the enemy nexus was destroyed, I looked at my cs and it showed 306. In the post game lobby it changed to 296.

Odd shtuff