Sorting NSFetchedResultsController by NULL NSDates

I have a tableview that loops through an array of data. The data is a set of contacts that may have a reminder time attached to them. For example:

• Jessica
• John
• Bill
• Katrina (February 9th)
• Brian (February 11th)

Right now, it sorts the tableview via the core-data attribute reminderDate in ascending manner. It works semi-correctly. The only catch is I'd like for the items that have a NULL reminderDate to be thrown to the end of the NSFetchedResultsController instead of at the beginning.

Ideally, it'd look like this:

• Katrina (February 9th)
• Brian (February 11th)
• Jessica
• John
• Bill

I can't use a comparative NSSortDescriptor as it's not supported by NSFetchedResultsController. Also, I'd rather not perform a sorting after I get results from the NSFetchedResultsController but rather before, when I make the query.

Here is the current code I use:

NSFetchRequest *fetchRequest = [NSFetchRequest fetchRequestWithEntityName:@"User"];
NSSortDescriptor *sortByDate = [NSSortDescriptor sortDescriptorWithKey:@"reminderDate" ascending:YES];

[fetchRequest setSortDescriptors:@[sortByDate]];
self.fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest
                                                                    managedObjectContext:context
                                                                      sectionNameKeyPath:nil
                                                                               cacheName:nil];

I believe I should be adding another sortDescriptor, but haven't gotten anything to work properly.