@Becky505
I'm not aware of any policy that says a host can cancel an IB penalty free if done within 48 hours, but maybe I missed something (I turned off IB a few months ago). From what I understand, only guests can cancel penalty free in the first 48 hours (if the stay is more than two weeks away) and that's not just for instant bookings.
Hosts can cancel an IB penalty free online three times a year (after that they have to contact Airbnb) if they feel uncomfortable with the guest or think they are going to break the house rules. However, if you're constantly cancelling, then Airbnb might withdraw your ability to use IB.
Here is the policy on that, which doesn't seem to have been updated since the new policy on penalties was announced:
https://www.airbnb.co.uk/help/article/2022/can-a-host-cancel-a-reservation-without-adverse-consequen...
What I did notice was different was that, in the new penalties policy, it says that hosts can cancel penalty free if they think that the guest will break house rules or throw a party. It doesn't say if the host feels uncomfortable with the guest.
Also, I was told by Airbnb that this would now apply to all bookings, not just IB ones, but that has not been stated in the policy so now I don't know if it's true or not. I have asked for clarification on that.