The three crew JFK summer time thing has happened ever year that we have operated JFK. Not saying I agree with it, but its not new. The 900hrs in 365 and 100 in 28 has also happened before, hence the spread sheet on the portal so if you have an incident when out of hours its your fault for not keeping an eye on it not the companies. Not agreeing with this either, but just stating facts.
I have had to cancel flights outa JFK in the past due to FTL, and I know many others that have done the same. Apart from the SNMC trying to miss calc the duty period while I was on the Sat phone, I heard nothing from the company abut it. I also ensured that the next departure time was not decided until all the crew were in the rooms at the hotel, also not liked by the SNMC at the time, but no backlash.
So know the rules and operate to them. If your out of duty your out of duty. Not your fault the flight is delayed. You help noone if you try and press on to keep the clown act performing smoothly. But if you are going to make the call, make sure you have worked the rules out corectly.
The Don