Operating Hours define when service resources are available for work and when customers can book appointments. The Time Slots for Appointment Booking setting determines how operating hours are divided into time slots that can be assigned to service appointments. The Maintenance Plan for the Account or the Due Date of the Service Appointment do not affect operating hours, but are used to generateand schedule recurring work orders. References: https://help.salesforce.com/s/articleView?id=sf.fs_operating_hours.htm &type=5https://help.salesforce.com/s/articleView?id=sf.fs_maintenance_plans.htm &type=5