The next rediscovery is changed based on the rediscovery interval and will be modified only after the next rediscovery happens.
Example :
Now :: 4:10 PM
Rediscovery interval Now : 30 mins
Next rediscovery : 4:15 PM
After Updating Rediscovery interval to 45 mins
Rediscovery interval : 45 mins
Next rediscovery : 4:15 PM
After rediscovery at 4:15 PM
Rediscovery interval : 45 mins
Next rediscovery : 5:00 PM
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Also Next rediscovery is read only. It displays the time when next rediscovery will take place and modifying it will not affect the underlying scheduler. (SDK allows to edit next rediscovery but the rediscover process will not take place at that time and next rediscovery will not be calculated from that time)