British Airways agrees to require negative coronavirus tests before New York flights

Once vaccines become mire widely available, look for international carriers to begin requiring proof of vaccination as a prerequisite to boarding an international flight,
Qantas has already made such an announcement. I also believe this has a chance to filter over to US Based domestic carriers and flights.
Cuomo is a grandstanding calculating political opportunist. His decisions and mandates are not based in science. They are decisions which placate and pander to his downstate voting base.

I'm betting the new strain is already here. It could have come in from any flight/ship/country. Maybe on the flights that brought in the vaccines. A negative test 72 hours ago doesn't mean a thing right now. Gov. Cuomo is doing his best but he's no scientist. At least he is trying to do something, unlike too many other politicians.