Frequent disconnects restarts since switching to XB8 modem

 For a test, does a computer / device that is hardwired directly to the router / gateway device with an ethernet cable have the same problem ?

With this test, we are trying to isolate this down to being either a WiFi-only problem or a problem with the general connection to the Comcast system which would of course affect both. It's a good first step in troubleshooting before proceeding any further. 

Hi there, and welcome to the Xfinity Forums community. user_j224t3. I completely understand how frustrating it must be to deal with WiFi disconnections—I'd be reaching out too if I were in your shoes. This definitely isn’t the experience we want anyone to have, and I’m really glad you reached out. You’re in the right place for support. We’ll ask a few quick questions to better understand what’s going on and work together toward a solution. To start, have you had a chance to try any troubleshooting steps using the Xfinity app? It’s a helpful tool that’s easy to use and often resolves common issues quickly. Have you noticed issues within certain rooms within your home?

@user_j224t3 

Have you had a chance to try that test ?