This issue has been discussed many times, most memorably in Escorted to leave prior to completing scheduled visit , and this bug seems to come and go as ABB update the site 
Welcome! We are a community of AirBnb hosts
This forum is dedicated to connecting hosts with other hosts. Sign up to get the latest updates and news just for AirBnb hosts! Note that we are not affiliated with Airbnb - we are just passionate hosts!