Found the answer at the Apple Developers Forum
First make sure that the detail view controller has a reference to the popover view:
- (void)splitViewController:(UISplitViewController *)svc
willHideViewController:(UIViewController *)aViewController
withBarButtonItem:(UIBarButtonItem *)barButtonItem
forPopoverController:(UIPopoverController *)pc {
//Grab a reference to the popover
self.popover = pc;
}
Then dismiss the popover when updating the detail view:
if (_popover != nil) {
[_popover dismissPopoverAnimated:YES];
}