Samwathegreat I believe you may misunderstand the issue. I have had the problems you refer to for years as a AT&T customer. I was a Comcast customer with a AT&T phone with the xfinity app installed on my phone and logged in. My phone would connect to xfinity hotspots and many time have had to turn off wifi because the xfinity hotspot was too weak. You may be able to fix that problem by uninstalling all xfinity apps.
My problem and I am sure a number of others in this thread happened after installing a new xfinity gatway. My phone would autoconnect to the XFINITY hotspot and I would not be able to download pics on text messages. Doesn't make sense to me, but that's what happens. And even though I went into setting and disabled autoconnect on the XFINITY hotspot it would connect. So by disabling the hotpots on my xfinity gatway I solved my problem.
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Here is the soulution. You are having this issue because your xFinity gateway is broadcast both "xfinitywifi" and "xfinity" hot spots. That's why you are seeing the hotspots on your phone. "xfinity" is a secure hotspot where as "xfinitywifi" anyone can log into. This is one way that Comcast is blanketing the area with hotspots. You have an option to turn off the hot spots that your gatway is broadcasting and thus will no longer have the issue with connecting to the xfinity hotspots.
Logon to your account and click on My Account and then click on Manage Internet and you will find a topic Wifi Public Hotspots. There you can disaable the public hotspots that your gateway is broacasting.
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