If you don’t fix the check-in the with her you are force to wait outside until 18:45 and when I was there it was super cold.
Since on the Airbnb site the check-in time is fixed at 15:00 ,on the description part it’s fixed by owner choice and I even proposed her if it’s possible I can come to your office in order to bring the houses key but the answer was always NO
I remained for 3:30 hours on the street on that horrible cold temperature