Recurring outages late at night
Last night around 3AM (PDT) my Internet service abruptly went out. I tried rebooting my modem and router and no effect: the "US" LED on the modem just kept blinking. I could ping my router and the local network side of the modem, but not 22.214.171.124. This is a recurring problem I'm experiencing: very frequently when I'm working late, my Internet service goes out for hours, and then returns by morning.
How do I track down the cause and stop the disruptions? Could it be from scheduled maintenance or something? If so, am I able to have Comcast notify of these maintenance periods in advance and let me ask to have them rescheduled to a more convenient time?