If I were in that scenario, and I were also an "at will" employee with "PTO" in lieu of vacation and sick leave, I would have started to take all remaining PTO

If I were in that scenario, and I were also an "at will" employee with "PTO" in lieu of vacation and sick leave, I would have started to take all remaining PTO upon learning the launch date would be pushed back. I would take care to work at least 8 hours in any calendar week, and work another 8 hours after all PTO had been used. After that, I would quit immediately--at 4:30 PM on that last day--and let my new employer know that I can now start before the previously arranged date. The careful use of time off is to maximize the amount of time being paid by the old employer with the minimum amount of effort wasted in throwing old tires onto the fire. If you are a salaried exempt employee, you have to be paid for the full week if you worked any of it. The PTO is just to mimic vacation, sick leave, and docked pay for not working a predetermined amount of hours in a week. If you leave with a positive PTO balance, unlike with vacation, the company does not have to pay you for it. So use it all up. Then work a bit more, so the company can't argue your quit date was the last day you actually worked. Depending on my financial situation and the corporate policies, I might actually start work at the new employer while burning through my leave at the old one. I would also try to find out if my new employer needed any more good people, and discreetly try to poach my most competent and amicable co-workers on my way out the door. If you're hitching a ride to flee a sinking ship, it's only fair to throw some flotation devices behind you as you sail away. A company that mismanages its tech professionals and its projects doesn't deserve diddly squat from you. If I were your new boss, I'd be glad that you're not spineless. That's like wondering whether the next person you date will think poorly of you for dumping your abusive ex. If they're worth keeping, they will applaud you for it.