Routing rule - default assignee and default team

Has anyone ever created a routing rule for a project with a default team AND a default assignee (where the default assignee isn't part of the default team?)

If so, do both the team and assignee get notifications?

I'm wanting to have a way that when one person from one particular team is out of office, a user can be added to the other teams routing rule just while they're away to be notified when new requests come through so I'm wondering if I can add that person as the default assignee just in that time?

Hope that makes sense