Have you checked the firmware at all?
I don't think I have any control over my router's firmware, and as far as I know my phone is up to date.
I had the chance to do some testing over at my parent's house. They have the odd situation of having two wireless routers, because when they upgraded their cable modem, they just kept their old linksys, even though they didn't technically need it anymore. Connecting to the linksys worked fine, and showed no signs of having my phone's connection lock-up. However, connecting to their Comcast router had a similar (though not exactly the same) lock-up occur. I didn't have forever to test, but it's looking very much like the router is at fault.
I suspect what changed is Comcast's recent "xfinitywifi" program, where they use their rented modem/routers as semi-public hotspots by splitting off a second network using the same antenna. Uses the same frequency and everything. This has not always been the case, I know for a fact that there was not an xfinitywifi coming out of my system as little as a few months ago. I'm guessing it started just a few days ago, when my troubles started. So, I think I have to call into customer service and tell them to disable it. You're supposed to be able to do that from the xfinity website, but I just get an error message when I try to get to that part of the account controls.
EDIT: tried getting into that control panel again, and it worked this time. Disabled the xfinitywifi from the website, and it actually shut it off on my router right away. Now to see if it fixes my phone's connection.
