I have 3 accessories (2 thermostats and one Sensiboo) exposed to HomeKit trough Home Assistant. My hub is a Apple TV HD 1st Gen.
I disabled the IGMP on my TP-Link and it resolved some of the “not responding” problems I got.
But I noticed that if I restart Home Assistant or change some settings the HomeKit integration seems to be reset. The devices are shown as not responding in the Home app and in HA I have notification for a new HomeKit bridge to be configured.