If this is an auction - assume 95%+ forgery or reprint
Amazing how many of these $500+ sets are available on auctions
If it's yours & you want an opinion - POLONUS (in the US) is probably the best place
Many expertizing groups will not touch these.
EDITED As you probably know since you collect Poland, the government reprinted 30M sets with the same dies & only the ink is different being brick red.
On the forgeries the serifs are "exaggerated" and on some the V in LEVANT is misshapen.
I believe that for the reprints & forgeries there is no fluorescence under UV light.