In a recent training session, an attendee posed the following question: Can you schedule recurring Skype for Business Online meetings for more than a year in advance? And if so, can this be limited by policy? The brief answer is: if you book the Skype for Business Online meeting in your Exchange mailbox calendar, then it is possible to book more than a year in advance. However, your approach might be different for other resources in Office 365 for which you can control and limit the ability to book ahead. For example, both room and equipment mailboxes permit the use of the BookingWindowInDays parameter of the Set-CalendarProcessing command in PowerShel. That parameter allows you to control how far in advance a resource booking can be made on the calendars of those mailboxes. The value for BookingWindowInDays can be set to between Zero and 1080 days, and defines how far in advance you can book that resource. A value of zero means: today. For example, the following command will configure the room mailbox “Large Conference Room” to reject a booking requested for more than 90 days in advance: Set-CalendarProcessing -Identity “Large Conference Room” -AutomateProcessing AutoAccept – BookingWindowInDays 90 The AutomateProcessing parameter shown above is set to AutoAccept by default for a resource mailbox – meaning that a room or equipment mailbox will automatically accept a meeting if it is in policy and then update the calendar. Whereas for a regular user mailbox, the default value for this parameter is AutoUpdate and cannot be changed to AutoAccept. This brings us back to the original question: the Set-CalendarProcessing command does not support setting policies on user mailboxes that prevent them from booking meetings (regular meetings or using Skype for Business Online) more than a set number of days in advance. More information on the Set-CalendarProcessing command can be found here. A key difference between the two scenarios is that the room and equipment mailboxes refer to physical resources of a limited number. You are not limited in the amount of Skype for Business online meeting spaces you can book, so there is no need to limit the ability to schedule in advance.