They are being put in low level quarantine
Is that everyone though? From what I heard from the meeting today, if people have plans and a place to go to self isolate, and aren't showing symptoms , then they will go into self isolation within a bubble of the person who picks them up from the airport.
Search on here for my post from safetravel. It describes the exact process including self isolation with police checks as well as what happens if the person doesn't have plans.