Why is the calendar module not showing all of my events from a synced calendar?

If you find that your calendar module only displays a year's worth of synced calendar events from the current month forward, it is due to several things. The most important one is that calendar sync can get quite large and take a long time to process. So syncs will only pull in a range of events ( 4 months prior and 20 months after ) from the current date. This will help keep the file size and processing time smaller.