What the hell does it matter??
If my employer says "you're full time, which means you work 40 hours a week" I can't just say "lol, I'm salaried, I do what I want, fuck you." nor can I say "lol, I get to choose my hours because I'm hourly, I only feel like getting paid for 30 hours a week, fuck you."
That's an extreme form of insubordination and it almost certainly means immediate dismissal.