Late for moronic Monday. Can those familiar with DOCSIS explain a few things?

We run a few branch sites over "business" cable DOCSIS w/ IPsec tunnel back to our main office. A few sites on Comcast and Spectrum/Charter.

Several times a year, our NMS shows latency/drop spikes, overall link quality issues. I monitor both our internal VPN address and the cable modem's public IP. I know it's an issue with the carrier network because the cable modem's IP shows loss/latency as well as our VPN interface.

Seems like every time I "escalate" to the ISP, they recommend (or even require) us to power cycle the modem before dispatching a tech on-site. In at least one case, a modem power cycle apparently did resolve the issue, as our NMS showed no issues afterward, and so far so good for a while.

Just now a Comcast tech told me they expect us to power cycle the modem at least once every 30 days to ensure they receive "updates."

to those familiar with DOCSIS: Is there any legit reason why a cable modem should need to be power cycled regularly?

Seems to me a working cable modem on good L1 path back to the head end(?) should be able to maintain indefinite uptime without issues. And if the modem did report issues, a reboot seems dubious at best to actually resolve the issue. Am I missing something?

P.S.: No, I don't expect any SLA from business cable, I know it's not enterprise-grade. Yes, I know ordering an EPL is preferred.