Well, I called back again, following the sacred FlyerTalk mantra and the agent quickly changed my flight to the 7am. She said the flight was changed by 3 minutes and that indeed made it an illegal connection. So she worked with a supervisor and confirmed the seats on the earlier flight. I think I should have enough time with an hour and a half between flights. As a precaution, I will try to make the 6 am flight as a standby but from a year of training I'd have to leave my house at 4 since I'll have to return the rental car instead of being dropped off at the terminal's front door.
On a side note...Where the heck is Terminal M in LaGuardia? Wouldn't it be Central Terminal Building and something like C10-14?
669 Departs
NYC/LAGUARDIA
TUE 22 NOV
7:00A
Terminal M