They are inserts of the Standing-O set. It is not a full 1:1 parallel as there are 126 cards in Standing-O and 84 in the die-cut set. Which UD says there is another insert set called World Premieres die cut, which there are 40 cards.
Tradingcarddb shows 126 cards for the die-cut parallel set, UD's number of 84 would make it 1:1 to the base set only and not the subset cards that are 85-126.
Ref:
https://www.tradingcarddb.com/Insert...ck-Standing-O!
http://sports.upperdeck.com/collecto...x?q=6&sid=9781