Gigabit service, IPv6, and Apple Time Capsule

I recently started the Gigabit service which became available in my area (north Phoenix). Service has been great up until about a week ago when I started experiencing intermittent connectivity issues and problems with my Apple Time Capsule which I use as my wifi access point off my primary router gateway. I have seen different issues on these topics in the forum so I am not sure what the cause of connection issue might be.

Couple questions. Has IPv6 been implemented in my area thus necessitating that my gateway router and wifi clients be compatible? Are there any settings e.g. DNS and/or IPv6 I need to change on the Time Capsule to get it working. My router gateway is assigned a public IP but my Time Capsule connected off the router shows "disconnected" for Internet. Right now I am not sure what the root cause is for my issue.

To troubleshoot I have bypassed all devices plugging a netgear router directly off of the gigabit fiber modem/device and I have no issues which leads me to believe the problem is with Apple device but I have read about different problems so I am uncertain. Any ideas or help??