Does anyone know what happened to flight 737 this morning? My dad was/is on it (YYZ-SFO on a 319) and said that after roughly an hour, they returned to YYZ due to mechanical issues and were met by fire trucks upon landing. Returned to the gate right away and awaiting a replacement aircraft to depart around 12:30. He said the pax received a $10 meal voucher, and he's now in the MLL- glad he's flying in J today. I'm currently in SFO awaiting his arrival. Anyone have any more info?