He's obviously thinking of Labor Day. I mix them up myself. I believe HN guidelines suggest steel manning here, not accusing him of being nonsensical because of a simple mistake.
Also, programmers often confuse Halloween and Christmas, because OCT 31 = DEC 25.
Not only are you correct (I mixed them up), but now I know about steel manning and am a fan. Thanks for the support and understanding - have a wonderful day!