Possible to set variable incremental availability during the course of a day in a single calendar?

I work in Education and i'm setting up a calendar where two types of meetings are available. 1 hour appointment slots and 20 minute appointment slots. I have set up two services and set up the appropriate increments for both services.

We would like the calendar to be restricted, for example - if one of our staff is scheduled to carry out 20 minute appointments in the morning, students should not be able book a 1 hour meeting with that member of staff in the morning. The same member of staff will then have 1 hour appointments in the afternoon so students should not be able to book 20 minute appointment in the afternoon with that staff.

The only way I think I can set this up is by having two separate calendars, turn the toggle off fo Use Business Hours for each staff, change the availability for each staff to match what I’m trying to achieve and split the two services across 2 calendars.

My question is: Is it possible to achieve this in a single calendar?