Boot File (not Firmware) Failing to Update on Arris SB8200

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This is rather frustrating and I'd like to share my experience so far since I haven't gotten anywhere and would like to provide some transparency to others who may come across this issue.

Before I get into the details, I just wanted to preface this by saying that the d11_m_sb8200_superfast_c01.cm file is NOT a firmware, but a boot file.  This was clarified via DM.

• On 8/29/2023, XfinityThomasC replied asking to send some signals to the modem, which would take the device offline. He also stated that if he couldn't resolve the issue that he was open a ticket to escalate the issue to upper tier support. He also asked if I had reached out to Arris directly.
• I replied back later that day confirming to proceed, and also indicated that I had not contacted Arris directly and I felt it was unnecessary since Comcast is my provider who is the one pushing out the update.
• Shortly thereafter, XfinityThomasC sent the signals, which ended up with the same results as I mentioned in the OP. He also suggested that I visit Arris' website to look for the firmware so that I may update the SB8200 manually, but I mentioned that there's no option to do that via the modem's GUI.
• On 8/30/2023, XfinityBillie replied asking again if I had contacted Arris by phone and asked if I was experiencing any connection issue.
• Later that day, I responded stating that I haven't contacted Arris by phone and that there were no connection issues other than the modem rebooting every night due to software update attempts.
• XfinityDanielB replied recommending again that I speak to Arris because he stated that Comcast only has the ability to send out a signal to automatically update the (latest) firmware, but a specific firmware cannot be selected to be pushed out.
• I asked for clarification regarding the d11_m_sb8200_superfast_c01.cm file 
• XfinityDanielB replied recommending that I replace the modem or reach out to Arris again because they would have more access than Comcast.
• Later that same day, I requested to have the issue escalated to the upper tier support since this low-level support kept trying to push me off to Arris instead of trying to help me.
• Shortly after, XfinityNicolas took over clarifying that the d11_m_sb8200_superfast_c01.cm file is a boot file and not a firmware. My use of the word firmware may have confused them, but all they had to do was referring to the log that I had provided above to know immediately the file I was referring to wasn't a firmware to begin with.
• On 8/31/2023, I replied back thanking them for clarifying the type of file that was being pushed out to the modem. I also offered to provide for details from the modem, including screenshots.
• A couple hours later, XfinityXanadu replied stating that error like what I was experiencing needed to be handled by Arris directly. He also stated, "we have no path of escalation when errors on the equipment side occur and it is not one of our rented gateways. On one of ours, we have full access to the build, setup, and back-end because we have a limited type of make and model". He then suggested that I call Arris at 1-877-466-8646.

That last bullet really upset me because it was a clear cop out response. Clearly, they do have full access to all their boot files. The modem sb8200 is even in the file name, and well as the plan that my parents are subscribed to. I'm unclear why this issue can't be escalated because clearly there's something wrong that doesn't need to involve Arris.

Regardless, I just got off the phone with Arris just to perform my due diligence and they basically redirected me back to Comcast. They stated that they do not have access to my modem nor are they capable of sending a signal to it. That makes complete sense, especially since Comcast is the provider and if a third-party could have easy access to my modem, that would be a cause for security/privacy concerns. I responded to the DM indicating that, and XfinityBillie just responded back with the following:

"Than k you for reaching back out. Since it has been 7 days since we last spoke may I please ahve your full name and the address for the account?"

Are you serious??? All my information is on the very first post at the top of the DM.

Here are a couple of links with other people who've experienced the same issue:

• https://reddit.com/r/Comcast_Xfinity/s/fVsIeGGLH3
• https://reddit.com/r/Comcast_Xfinity/s/yN6JKwlGjl

FWIW, just for the sake of general information and clarity here. It actually is the software / firmware load that is failing to update. But it's being caused by the config / boot file. They are attempting to update the firmware via NMS and via the boot file but the file is either missing data or has incorrect manufacturer / vendor specific CVC certificate data, so the validation process fails. 

The modem should continue to work fine even without the firmware update. Honestly, if there are no connectivity problems, there's no need to sweat this. These things have a way of ironing themselves out / going away eventually. Good luck !