C6300 - Internet Disconnecting

Have the ISP check the signal and line quality UP to the modem.
~ISP has been to the house twice - the signal and line from street to modem is fully intact.

Be sure the ISP provisions the modem correctly.

~ISP has provisioned and reprovisioned with no changes.

Be sure there are no coax cable line splitters in the between the modem and ISP service box.

~We moved modem previous and had an open output on the splitter. The modem has been returned to original location and the output has been closed. The line from the street comes into a 3/2 splitter with one line going into the modem.

Be sure your using good quality RG6 coax cable up to the modem.
~Affirmative.

Be sure to power OFF the modem for 1 minute them back ON.
~ It has been de-powered several times (for one minute, ten minutes, and had a factory reset) - no change

Observations:
-Disable Port Scan and DOS Protection on settings is not checked and enabled
-Nighthawk app says my firmware isn't updated, but the version reads as most recent V1.03.04.
- This def a consistent "12-hour" drop which lasts for about 3 minutes and it takes my systems another 6 minutes to come back online. No other drops are taking place though.

Questions:
Do you think DDOS and DOS attacks are impacting anything (as they seem to be quite excessive/consistent on the logs)?
Any value in asking netgear tech support to escalate this up a tier?

THANK YOU FOR YOUR REPLY -