T3 error 4:30 AM every day - daily maintenance?

Since I have been on mid-split upgraded service with a Netgear CM3000 for about 6 weeks or so, everything has been working fine except for one curiosity. Every morning at 4:30 AM, the modem log reports a T3 error. This never happened prior to the mid-split/CM3000 install.

It's just one T3 - and it's literally from 4:29 AM to 4:31 AM local time every single day! Most days I get no other T3 errors, maybe some days I get 1-2 throughout the day - that's expected I think.

This obviously doesn't impact our network operation in the house, but I am very curious what it could be. There is nothing on a timer in the house that could be setting it off with a power surge or something - no lights, water heater, heat/AC, appliances, TVs, etc. The cable from outside is very clean inside our house, and is not near anything. Outside the cable goes up to a pole.

There are never any uncorrectible errors on the modem page, and in a week there will be about 10-15 correctible errors on about 10 downstream channels. Also, SNR are excellent (~44 on all channels), and power levels are well in spec. There are no T2, T4, MDD, TCS partial service, or other errors in the modem log. So it seems to be a very clean line. If there was some sort of power surge inside/outside the house causing this, you would think it would happen other times of the day as well.

I was told on Reddit by a CC employee that this is a daily maintenance reboot. Is this due to mid-split, as this did not happen before? Or are they tweaking things every night? I just wanted to double check that answer, as it did not do this before ;-)

Thank you!