Oop! Skimmed that thread, missed the post in question. However, I get the impression from the latest L.A. Times article that they are calling the box set "I Love Lucy: Seasons 7-9."
The L.A. Times had an article today about the Museum of Television and Radio showing the "I Love Lucy Movie" Friday night. For those who don't know, it was cobbled together in the early '50s from three episodes of the show, plus additional linking footage shot specifically for the movie...