Several years ago, the SNMP Collector was refactored to track the sysUpTime change on each collection attempt. That functionality was integrated with another feature which is disabled by default, so the sysUpTime check is not being performed.
This feature is send a forceRescan if a change is detected on the ifNumber or the sysUpTime, that for some reasons has been disabled.
The validation of the sysUpTime must be executed no matter if the forceRescan feature is enabled or not for the SNMP Collector, in order to skip the persistence and the threshold processing for counter variables.
Because this is not happening right now, the counter variables may have big spikes due to counter resets, and the threshold processor may generate invalid alarms.