When Lela is trying on outfits from Mack's closet all of the clothes are transformed into a garb that would be worn in the year that Lela was from, 1962. One of the outfits that she came out with was the signature pink pillbox hat and suit that Jackie Kennedy wore the day of her husband's assassination. But this did not happen until November of 1963- one year later.
Maia Mitchell and Ross Lynch kissed as their roles of Mac and Brady in Teen Beach Movie (2013), even though it wasn't on the script. The kiss didn't make the final cut though.