The "Receiver Status -> Activity" page on the NetRS shows the "Run Time" - the length of time since the receiver has last rebooted.  However if the receiver has been operating continuously for more than 497.1 days, the counter will reset to zero without a reboot occurring.  For example, a receiver that was last rebooted 597.1 days ago would show a Run Time of 100 days.

This is the result of the way uptime is stored in a standard linux kernel: as an unsigned long (32 bit) counter and counts a 100 Hz clock.  Therefore, the 100 Hz clock rolls over after…
0.01  * 2^32 seconds
497 days 2 hours  27 minutes 52.96 seconds

This is known in the IT world as the "497.1 Day Bug", and while it has been observed to cause problems in some computing applications, no ill effects have been observed in our NetRS networks.