Nmap takes double the time specified to mark device away


I’m starting with nmap integration, and according to my tests, it takes twice the time specified in scan interval to mark a device as away.

If I scan every 20s, it takes 40s after the last seen time to mark it as “away”.
If I input 60s, it takes 2 min to mark it as away.

It’s like it always wait for 2 consecutive failed scan before marking a device as away.

Can someone confirm if this is a bug?

Thank you