Hi philipni,
you have resumed a very old discussion
Octane v3/4 licenses are floating, and automatically deactivated on exit, ready to be instantly activated on another machine.
You can always manually deactivate all your licenses by pressing the Sign-out button in Standalone/File/Account panel.
The 5 web unlocks are necessary only in extreme cases, when the active machine has crashed, or no longer exists, due to a complete system reinstall, for example.
So you can install Octane on several different machines, but you can use your Combo licenses only on one machine at a time.
You need a Combo license Standalone + plugin for each machines that need to work simultaneously.
Happy GPU Rendering,
ciao Beppe