When flying from Merced to Guanajuato, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
Merced Municipal (MCE) is the airport you will fly out of if you book a flight from Merced to Guanajuato. You should not have trouble finding flights to Guanajuato from Merced Municipal; the airport handles an average of 0 outbound flights to Guanajuato per day. You should also have plenty of airline options to choose from since 0 airlines have flights from the Merced airport to Guanajuato. It is only a 2.1 mi journey to Merced Municipal (MCE) from Merced’s city center.