Check in really confusing, I instant booked and paid for the night (around 5:30pm). I was then emailed instructions to contact reception (that is now closed) or message if afterhours... No response for a couple of hours and I needed somewhere to stay.
Contacted Airbnb support, the reviewed the listing, my correspondence and also tried to contact the host. Due to no response Airbnb support cancelled the booking and refunded me.
Recommend on any instant book, after hours self check ins to contact the host and confirm details BEFORE you pay. To ensure it is actually after hours self check in.