Hi Don Hauri,
Greetings from Syncfusion.
As per Scheduler design appointments will occupy the time slots based on start and end time, each time slot having the same height based on TimeInterval value so we cannot increase height based on appointments count in day view. And also, if we arrange the appointments in vertical, appointment resizing cannot be done.
But we suggest that you can use SfScheduler TimelineView, in which timeslots are arranged in horizontal and appointments are arranged in vertical. Kindly refer our UG documentation to know more about TimelineView of scheduler.
Please revert us if you have any concerns.
Regards,
Karthik Raja A