I really have no idea which board this should be on. I can't find anything similar. I just know I have a Pixel 5, new Nest wifi router, and presence sensing set up in Google Home. I have it turn on/off 3 lights, which works instantly from Home app.
But when I come home, phone immediately connects to wifi, but Presence doesn't change to Home for a couple minutes. Before then I need to turn lights on myself, which ruins the point. Why could it be so slow? You would think as soon as I connect to wifi, that's a pretty good indication I'm home. I live alone, no one else is setup.
Sorry to hear about the issues with your presence sensing being slow, I'm sure it's confusing, but I'm happy to help.
Have you tried uninstalling and reinstalling the app? If you have done that, I would suggest sending feedback to our engineering team through this link so that they can investigate this.
Please let me know if you have any further questions.