If you're coding, interesting numbers will show up sometimes!
49 days = 49 days * 24 hours per day * 60 minutes per hour * 60 seconds per minute * 1000 ms = 4,233,600,000, or 0xFC579C00, or close to 0xFFFFFFFF. In other words, some unsigned 64 bit millisecond counter just overflowed.
Same story here, except that is an signed 64 bit millisecond counter.
|86400||Number of seconds per day|