There are multiple versions of the AirBnB host interface out there, but here's how *I* can reach the BTR stuff for my listing:
Open your Dashboard. Click on "Your listing", which will open your calendar. Near the upper left, click on the unlabeled button that has 4 horizontal bars. In the menu that slides out, scroll down to Business Travel and click on that.
Keep in mind that, regardless of your high-ratings, etc, there are various things that might make you ineligible for the BTR designation. (In our case, it's because we have dogs on the premises.)
If that helped, hit the thumbs-up below.