1959 Home Run Derby - why not "1960?"

[JLange]

A thread about mis-dating the 1937 Goudey wide pen premiums for Feller and Doerr to 1936 got me thinking - why is the Home Run Derby set dated to 1959? The card for Rocky Colavito has him on the Detroit Tigers - a trade that took place April 17, 1960. Why are these not dated 1960? I saw several HRD threads in archive but didn't see this issue addressed specifically. Thoughts?

[ALR-bishop]

Somewhere I have seen an article on this point. Am trying to run it down

[JLange]

Ok, I've read that the home run derby show was taped during the 1959 season, and began airing after the season ended and into the following year. Even if the cards were from the 1959 season, the Colavito (Detroit Tigers) card still points to a 1960 issue date for the card set. We don't say the 1960 Topps set should really be 1959, since the stats, photos, teams, etc were from the '59 season. Is it possible the cards were issued only a few at a time to coincide with the latest episode beginning in Fall '59 and continuing into '60, and Colavito's episode appeared only after his trade occurred in April 1960? Even then they should be listed as 1959-60. What am I missing?