If you are not familiar with router configuration and networking, it might be best to not switch off Verizon router.
Verizon will not support anything other than using their router. So if you have an issue, you will be left with either going back to the person who swapped it for you, or trying to figure it out with online help.
There is a thread at the the top of this forum on how to configure your own router for use with FIOS including TV service.
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