My Wemo app displays "This Wemo (hub) isn't responding". Eero has it as active on the 2.4GHz network (not grayed out). Ping requests timeout. If I pause the 5GHz band it starts communicating again. When I unpause the 5GHz band and after a set interval, about 5 minutes, it loses communications again. I am running the current SW V7.1.1. Older versions did this too but seems to be constant with this SW version and SW 7.1.0. On my old router I setup 2 SSIDs, one for 2.4GHz and one for 5GHz to minimize issues like this. I explored all setup options and cannot find anything to eliminate this device loosing communications. Any suggestions?

I would suggest that if it is technically possible that you allow a guest network to be setup exclusively with a SSID using 2.4GHZ, also recommended by Bill (another post 1 month ago).  This would also help secure the primary SSID from access from the older unsecured legacy devices.