I don't need the logs, but check the date and time on them. One is generated per power cycle, so if there is only one with a date/time covering your flight then it didn't reboot. If it did reboot, there would be a second, or more, file(s) started each time it powered up.
So for the last flight where you had problems, how many track log files are there for that day, and do the timing look to be about right if more than one, or when you think it rebooted?