I moved to a new house, taking my existing Eero setup, and experience connection dropouts.
I had Virgin Broadband and the old house, and the new house, and assumed I would be just plug and play.
I tried setting the Eero system in bridge mode, which didn’t solve the problem entirely, but did help.
The solution in the end was to set the Eero system to use the Manual IP setting, so that’s its IP range was 10.0.0.x.
This left the Virgin router to use the 192.168.0.x range.
I think the problem was IP address collison.
This also left me able to connect directly to the Virgin router Wifi if I need too (for high speed downloads), as the Eero didn’t give the full speed of the Virgin Router.