category code on green card

I just notice that on my father's green card, the category code is CU6, however, the category code on the approval notice is IR0. The codes on my mother's green card and the approval notice are both IR0. The only difference between their cases is, my mom's name check is cleared, my dad's name check is still pending.

I googled the code CU6 and found that the code seems to be used for Cuban citizen when they become lawful immigrant in US. If this is the case, what should I do now? Contact USCIS? InfoPass? Any suggestions?

Anybody with name check still pending and got green card after the memo, could you please check your category code on your green card and approval notice? Are they the same?

Many thanks in advance!