A quick question on changing admin users/domains

This is a bit unclear to me, so I’m confirming. When I edit the user that a domain is mapped to, the site is then hosted on the virtual machine that user/admin is assigned to.

I’ve wanted to rearrange where things are hosted to better organize my domain, but never shuffled admin users about, but am merely confirming I’m correct. A bit of pre-emptive paranoia.

(Too used to working on non-virtual machines I suppose).

Correct. Your user has a folder on a virtual machine. “Mapping” a domain to that user basically creates a sub-folder for that domain.
You can use the same user account for several domains, which can make life easier for many things.

Thanks for the clarification. So basically that’ll let me distribute my sites to new VPSes pretty easily and in a nicely owner-targeted manner.

Correct. When you are creating the new user, you should have a drop-down to choose which VPS or Hosting plan that user will be on.
Then when setting up the domain you choose which user that domain will be on.

So: VPS> User(s)> Domain(s)