I have had my iPhone5 since December and have used the calendar as a daily diary to chart all meetings. Suddenly I have noticed all of my entries from December to June have disappeared! Only the recurring entries remian. Can I get them back? I am doomed work-wise if not.
The iPhone is really designed as a forward-looking device regarding calendars. You can prevent this behavior (of events falling off the calendar) in the future by doing Settings > Mail, Contacts, Calendars > Sync (scroll down to see this) = "All events".
That may bring back your old events depending on where they were stored.