I'm back from a 5yr gap and would like to dismantle my node network - can it be done en masse or do I literally have to go to each node in the map and deselect it from there?
A value pack allows node management (investment) from the world map. You can get a one day value pack for 2800 loyalities. Not sure if that's needed just to remove CP investment.
You can retrieve your invested CP via map any time free of charge. If you have spend energy on the node its still there when you reinvest again.
No other, faster way.