I'm having the same issue using a Negear R7400 with the gateway usedwith the business service. The gateway is in bridge mode and for some reason the internet dies periodically. Rebooting both devices seems to fix it. Last night it did this around midnight, I just let it sit and by morning the internet was working again.
For me, it doesn't seem to be according to a reliable time period, it's more random. Also, it took at least more than an hour before it "fixed" itself and internet returned.
