@Mary4736 Yes, you would choose X and that will block the chosen dates.
I just double-checked to see how it looks on my desktop calendar, and for some but not all dates there’s a new (and confusing) set-up! After selecting the dates you want to block, you just see “Availability” and beneath that, “Open.” To the right is the word “Edit.” Clicking that will bring up a frame that allows you to choose either “open” or “blocked.”
I never like it when they add a step to the actions hosts need to take…