What's the difference between Check available and the actual check

Check issue is less the Available funds

[security56]

Hi today I saw that check is already pending, but its less then the actual available funds for last month, but in the main publisher screen still shows that actual amount of last month.

Does this mean that the check issue number is wrong or that they will give me the rest of the money next month :)

Its's not much of a difference but I am still curious.

Thanks