As of January 1, 2021 NortonLifeLock and Comcast have terminated their partnership in relation to Norton Security Online and Norton Security Suite. An email communication has been sent out by Comcast to all the Comcast customers explaining this change. As a result, your current NortonLifeLock subscription that is provided by Comcast will be canceled effective December 31, 2020.
How can I continue using my NortonLifeLock subscription?
You can continue your NortonLifeLock subscription after your current Comcast subscription ends by enrolling in a NortonLifeLock plan. Once you receive a confirmation that your account has been canceled, please visit http://norton.com/xfinity6 to enroll.
Do I need to cancel my existing NortonLifeLock subscription?
Comcast should cancel your subscription. If your subscription is not canceled, please contact Comcast at 1-800-XFINITY.
If you have any issues with your existing Comcast account, contact Comcast."
Some addtional info I have located:
Effects of Expiration
Some anti-virus programs differentiate your subscription from the software itself -- even after expiration, you can continue using the program with old virus definitions. Norton, however, disables the entire program when your subscription runs out. You can't run scans or enable background protection in Norton without a current subscription. This prevents users from mistakenly believing their product will continue to work effectively without new definitions, but it leaves your computers vulnerable until you fix the problem.
I know not much more assistance than what we have already received from Comcast - but Norton did respond to my question to their forum admins:
Norton never releases dates for changes, as they can change in a nanosecond - so I will say that if things go as planned as of the date/time of this posting:
Norton will begin to deactivate your Comcast's Norton Security Online on 7 January 2021.
This will be a "throttled removal" and could take into the month of February for it to be totally completed. In regards to throttled it is basically to control "call volume" to Support. As we all know there is nothing worse than having to "hold" for support. If the volume is too heavy, the deactivation process can be throttled back to a slower deactivation schedule.