We've changed the way you access availability settings. They have been moved back into a button. Previously the settings were in the side bar which many users did not find intuitive (especially on mobile).
This change also merges event duration, padding, and max guests with the availability settings, so as to bring them all into one place: 
As a result of the merge, we've added more granular copying. Now you can choose which settings to copy to other event types.
