Joseph, they often didn’t decide whether to make a leap year until late Adar, sometimes as late as the 29th. Once it even happened that they did it on Rosh Chodesh which would have been Nissan, but chazal disapproved of that.
Mobico, having read the lawsuit I don’t believe the plaintiff is dati.
Reb Eliezer, I don’t follow your reasoning. You say the idea is dangerous because if they did it we’d eat chometz on pesach. But if they could do it it would be Purim. The problem isn’t that doing it is bad or dangerous, it’s that the people who can do it aren’t available. There was still time for them to reassemble and do it until tonight. Now it’s too late. Even if Moshiach comes tonight (US time) it’s already rosh chodesh Nissan and therefore too late to make it Adar.