Can't connect to local network for several minutes after reboot, and other strange network issues

Hi all,

Thought I'd post here before other Mac subreddits, considering this is only happening on my late 2013 Mac Pro running Sequoia via OCLP.

First is that on reboot I can't connect to any of my self-hosted services, router, or other machines on my local network. This is across multiple vlans, but always within the bounds of my home network (e.g. 192.168.1 - 192.168.6 subnets). This happens for any type of service I try to connect to on my home network, regardless if that's http/https, ssh, vnc, etc. and also whether it's by DNS or IP. The extra weird part is that some connections work, as I'm able to browse external websites which would require traffic from my Mac Pro to get DNS from my PiHole instance (local) as well as traverse through my Ubiquiti router (which I can't connect to via https in a browser). After ~2 - 3 minutes with no changes or action on my part, any local connection I try to make start working again. To be clear, there are no errors being generated by my local hosted services - every error I get is a connection timeout. At the same time my Mac Pro can't connect, I've verified that other hosts can in fact connect to these local services.

I don't know if this is related or not, but WiFi doesn't work at all - it connects to my AP, gets all the same DHCP info that the ethernet connection gets, but won't connect to either internal or external network nodes. That being the case, I keep WiFi turned off, and I exclusively use a wired connection. As the Mac Pro has 2 ethernet ports, I've also tried switching the port, but I still get the weird issue I mentioned in the 1st paragraph.

This is on a fresh install of Sequoia. I had a bunch of testing and dev tools on this machine previously and it had gotten a bit crufty so I did a drive format and install when switching from Sonoma to Sequoia. Part of the reason I did so was this issue was happening on Sonoma as well. I don't recall if it also was happening on Ventura, but I don't believe it was. I don't have any special firewall settings or network settings going on either.

Any ideas?