Orbi RBR850 - SPC/Circle MISTAKENLY activated - Cannot set custom DNS servers?

Hardware reference: One Orbi RBR850 + two synced Orbi RBS850 satellites running Netgear firmware version 4.6.3.16_2.0.51. Windows 10 PC using Firefox v92.0.1 and Chrome v94.0.4606.61 browsers to access the Orbi RBR850 web configuration GUI.

Fundamental issue is that I cannot set custom DNS servers on my RBR850 in the web GUI. Custom DNS servers WERE SET previously in the RBR850 device configuration BEFORE accidental SPC/Cirrcle activation.

I MISTAKENLY activated Netgear Smart Parental Controls/Circle from the Orbi app in a dark hazy morning brain fog while fumbling around with the app. I sent email to Netgear Support asking to CANCEL / DEACTIVATE the accidental SPC activation. I received a convoluted email reply from Support containing numerous misspellings and grammatical nonsensicals that did not make it clear in the reply if the SPC/Circle activation was actually cancelled / deactivated on my account & Orbi RBR850 device, or not.

Referencing the Orbi app it is evident that the SPC/Circle activation is NOT cancelled / deactivated but is still ACTIVATED on the registered Netgear account and the registered Orbi RBR850 device. I can't get any further reply from Support re the SPC cancellation request because the original support case was closed following the unclear email reply - followed by a further Support explanation on telephone "...you dont' have an active support contract on your [<1 year old] registered RBR850 device".

WTF?!?!

Reading the numerous threads in the Netgear Community and other various online forums re SPC/Circle conflicting with custom DNS server settings on Orbi devices it appears that the SPC/Circle activation on Orbi devices REMOVES the option to set custom DNS servers from the web GUI. Apparently, SPC/Circle relies on it own DNS servers for DNS filtering to perform the Internet Nanny functions?

So, as mentioned in the various threads and forums as the solution to restoring the DNS servers setting availibility in the Orbi web GUI, I DISABLED SPC from the app, power cycled the modem, power cycled the RBR850, and returned to the web GUI hoping that process resolved the DNS server settings availability issue.

Nope!! No luck!!

The custom DNS server settings availability is still greyed out in the Orbi RBR850 Advance/Setup/Internet Setup tab in the web GUI - even when the 'Use Static IP Address' option is selected.

So, in the continuing effort to resolve the custom DNS server settings availability issue I VERY RELUCTANTLY performed a FACTORY RESET on the Orbi RBR850 and the two synced Orbi RBS850 satellites and went through the network setup process again. That factory reset process was a MAJOR PIA as it wiped out ALL of my previous global network customizations. And... NO CHANGE TO THE DNS SERVER SETTINGS AVAILABILITY IN THE WEB GUI!?!?!

Again... WTF?!?!

So, the fundamental question is...

How can Netgear SPC/Circle be DEACTIVATED / DISABLED / REMOVED sufficient to restore custom DNS server settings availability in the Orbi RBR850 Advanced web GUI?

Alternatively, how can the DNS server settings be hacked / customized and saved to the Orbi RBR850 device if SPC/Circle cannot be deactivated / disabled / removed?

Thank you in advance for the help!!