I can tell you that based on whom is in the set.
https://www.beckett.com/baseball/197...s-police-pink/
https://www.psacard.com/auctionprice...oe-foy/2523122
Both McLain and Foy only played for the Senators in 1971 thus they can't be 1970 cards.McLain was 3-5 for the Tigers that year with the gambling suspension and Foy was coming from the Mets,
So, the Pink has to be from 1971 unless they were psychic as to whom Robert Short was bringing to the Senators the next season.