I'm using my LEDE router to track presence in Homeassistant. It uses luci-mod-rpc to see if my devices are connected to my wifi by checking the arp table.
This works well for my android devices, but for some reason it doesn't for my iPhone X. If ssh into my router and run arp, I can see that the flag of my android devices change from 0x2 to 0x0 (connected to disconnected I suppose?) when I disconnect from wifi, but the flag of my iPhone X often stays on 0x2, and thus Homeassistant keeps on showing it as home, while it's not connected.
Once it missed my device going offline, it will keep on showing it online (flag is 0x2 in the arp table), until I reconnect and disconnect again (unless it fails again, of course).
I don't really know if this is a bug in LEDE, a wrongly use of the arptable by Homeassistant or something wrong with the iPhone X, but it's very annoying and I would like to find a solution