The calendar drop down will show 6 months in advance. If something is needed to be seen past those 6 months, the user can select the most future option from the drop down menu and then the drop down menu options will change. The options will show 6 months in the advance from the newly selected date. 

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For example:
The calendar is currently set to May 2015. The drop down shows in the future until November 2015, but the user needs to see an event in December. 
Select November 2015 from the drop down menu. Once the page reloads, select December 2015 from the drop down menu to see that calendar. 

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