Assad is sending his chemical weapons to Hezbollah:
http://www.jpost.com/Middle-East/Report-Syria-is-transferring-chemical-weapons-to-Hezbollah-to-avoid-international-inspection-326236
Could be the reason behind this change in Israeli policy.
The significant question to be asked at this point is what could bind Israel, Turkey, Qatar in a form of unholy alliance on the one side, and Assad's Syria, Iran, Russia and China on the other side, in such deadly confrontation over the political future of Syria? One answer is energy geopolitics.