Can on-premise Exchange calendars connect with Free/Busy Calendar Access Mode?

Free/Busy Calendar Access Mode is only available for Google and Microsoft 365 calendars. It isn’t available for on-premise Exchange.

On-premise Exchange calendars connect with Read-Write access, either through Individual Connect or Enterprise Connect.

If an organization’s policies only allow Cronofy to see free/busy information, its Exchange admin can limit the Enterprise Connect service account to free/busy access. Your application then requests the free_busy scope, as described in Free/Busy only.

These connections are read-only, so the Create or Update Event endpoint can’t be used with them. Instead, you can send the user a Smart Invite.