It would be very useful to have the ability to choose between 12-hour (AM/PM) and 24-hour time formats in the calendar booking interface.
Many users, especially in Europe and other regions, are more familiar with the 24-hour format, and the current 12-hour time picker can create confusion for clients when booking appointments.
Adding a simple setting to switch between 12-hour and 24-hour formats would greatly improve usability and user experience for both businesses and their customers.