Hello @Elle2,
I'm aware you are a CA and that is why I said, let's hope for a response from a CA host which would be more reliable.
However I'm more inclined to believe what Jace is true that airbnb absolutely does not override California Law.
You can quote the law and inform the guest that an Airbnb supervisor (Jace) has told you that Airbnb Terms do not override state law. And thus your are allowed to bring in prospective tenants with a 24 hours notice.
Long term rentals on Airbnb often come with such issues that is why most hosts avoid long term bookings.
Hope you this gets resolved.