I noticed this several times recently. Today I figured out that the disruption affects only 5GHz connections. WIred connections and 2.4GHz WiFi operates normally with no disruption.
This time the 5GHz interruption cleared itself after 22 minutes. I did not reset anything, but I maybe it kicked something when I logged-in to the web setup and checked for updated firmware. The router's internal web page reports that it's currently using "V1.0.9.88_10.2.88" firmware and no update is available.
The device my brother is carrying when he drives away is a Samsung Galaxy Note 9.
I found discussions suggesting that I downgrade to an older firmware to prevent random 5GHz disruptions. I don't know if they ever discovered a correlation to a client device leaving the network range. Maybe this observation will lead to a proper fix or work-around without installing an out-dated / insecure older firmware.
> [...] The router's internal web page reports that it's currently using > "V1.0.9.88_10.2.88" firmware and no update is available.
Trust no one, I always say.
Visit http://netgear.com/support , put in your model number, and look for Downloads. (For older versions, under Firmware and Software Downloads, look for "View Previous Versions".) Find the kit(s). Download the kit(s) you want. Read the "Release Notes" file for instructions. (In the User Manual, look for "firmware", and, especially, for a topic like "Manually Upload Firmware to the Router".) When that fails because of a deficient User Manual, try:
