I can see a few posts over the years discussing this but it doesn't seem like it was ever answered fully?

Is there a way, or are there any plans to allow, a single requestor to be at multiple sites? It seems strange that this isn't possible, as many businesses have staff that work across multiple sites now.

E.g. a roving engineer who goes site to site fixing machinery, or in our case teachers who work at multiple schools.

It is a very common use case.