do I have the latest update on my G36

If you are referring to firmware updates DOCSIS standards dictate that the service provider must distribute firmware updates to cable modem devices.  The end-user cannot simply install an update like most other network-enabled devices.

ARRIS develops the software update and makes it available to service providers.  The service providers qualify, test, and distribute the software update to devices on their network.  ARRIS has limited control or visibility on distribution by the service providers.

When the internet connection drops, does it seem like the gateway is rebooting on its own?
Also, do the connection interruptions occur on both Ethernet and Wi-Fi? 

Cable Co.= Comcast/Xfinity, they have replaced everything they can, even new cable boxes that work off Wi-Fi. Still getting picture pixelation, audio drop and some freezing. not all time, but seems to happen when we sit down and watch a program around 8:00 PM on local channels. The next step for the cable co to replace my router with their own, to see if that will work. My G36 is out of warranty as of April 2025. Also sometimes when I use my computer, It will go off line for a few seconds. Not sure if it is rebooting on it’s own, but I have rebooted several times in hopes that it will fix any problems.