I bet they're not. There is no longer any way in this world to launch an invasion without it being detected weeks in advance. The information system, the enemy within, and the urge to expose is too powerful.
Plus, there's the political urge to make the case for invasion before it happens.
All bets are off if Syria decides to get involved with the Gaza situation. I bet that scenario is being bounced around between Israel and USA. We already have troops on the border with Syria, that's for certain.