SN74AUP1G08: SN74AUP1G08DCKR - DIE CODE DIFFERENCES

We recent bought SN74AUP1G08DCKR from distributors and realized differences in DIE code.

Can i check if both die codes are valid? is there any PCN on these differences? 

Both are COO China and DC21+

DIE CODE = HEC - is this valid ?

Thanks

Calvin