Hi @Vincent833
I believe the smart lock integration with Airbnb allows you to set the access codes to only be active at check-in time and automatically expire at check-out time. This way, even if the guest has a door code 48hrs prior, it will not be active until their check-in date/time. I would read through all the information about smart lock integration in the Airbnb Help articles before connecting a lock to avoid issues. Below is the info on how the lock access is scheduled:
Setup & Manage Smart Lock
https://www.airbnb.com/help/article/3481
That said, there have already been some issues with the lock integration, so it might be advisable to wait until the "kinks" are worked out?