I just solved my own Vulcanus UPS bug, it looks like demolishers cause FPS and UPS issues.
I may be wrong but I think avoiding areas with many demolishers and not having a lot of radars helps.

I started experiencing extreme lag 2 days ago on a server me and my family setup. The lag started when my cousin started exploring more of Volcanus.
I downloaded the map and tried playing it locally and I get UPS of 45-50.
It was only the 2 of us online when this started happening and we where not ...