Knowledgebase: iPad/iPhone/iPod touch
iPhone monthly recurring events occurring on the 31st of the month
Posted by - NA - on 30 June 2009 04:35 PM
Monthly recurring events for the 31st of the month, created on the server or the device, appear on the iPhone/iPod touch/iPad calendar only in months with 31 days. 
On the server or in Outlook, the events appear on the last day of the month regardless of the number of days in the month.

Furthermore, the event will appear for the number of occurrences specified, but only in months with 31 days. 
Example: Create a recurring event for the 31st, starting in January for ten occurrences.  On the server, the event occurs on the last day of every month through October.  On the device, the event appears in the seven months that have 31 days and then in January, March, and May of the following year.