I think he may have been alluding to the fact that if he was out at sea, middle of the night, he would have had to fly for longer than the standby power system supplies battery power to the standby instruments.
When the juice has dried up, I think it would be a little challenging flying at night with only a magnetic compass, no A/H, and basic pressure altimiter and airspeed. No comms, or nav aids, foreign country. Not impossible, but pretty difficult.