@interface ModelA : RLMObject
@property int pk;
@end

@implementation ModelA
+ (NSString *) primaryKey
{
    return @"pk";
}
@end

@implementation ViewController
{
    RLMNotificationToken *_nfA;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    RLMRealm *realm = [RLMRealm defaultRealm];

    [realm beginWriteTransaction];
    for(int i = 0; i<10; ++i)
    {
        ModelA *a = [[ModelA alloc] init];
        a.pk = i;
        [realm addOrUpdateObject:a];
    }
    [realm commitWriteTransaction];

    _nfA = [[ModelA allObjects] addNotificationBlock:^(RLMResults *results, RLMCollectionChange *change, NSError *error)
    {
        if(change)
        {
            NSLog(@"Insertions: %lu deleteions:%lu modifications:%lun", change.insertions.count, change.deletions.count, change.modifications.count);
        }
    }];

    for(int i=0; i<10; ++i)
    {
        RLMRealm *realm = [RLMRealm defaultRealm];
        [realm beginWriteTransaction];
        [realm deleteObject:[[ModelA allObjects] objectAtIndex:0]];
        [realm commitWriteTransaction];
    }
}
@end

2017-01-20 10:44:19.394 Test[7536:12871658] Insertions: 1 deleteions:2 modifications:0
2017-01-20 10:44:19.395 Test[7536:12871658] Insertions: 1 deleteions:2 modifications:0
2017-01-20 10:44:19.395 Test[7536:12871658] Insertions: 1 deleteions:2 modifications:0
2017-01-20 10:44:19.396 Test[7536:12871658] Insertions: 1 deleteions:2 modifications:0
2017-01-20 10:44:19.396 Test[7536:12871658] Insertions: 1 deleteions:2 modifications:0
2017-01-20 10:44:19.397 Test[7536:12871658] Insertions: 1 deleteions:2 modifications:0
2017-01-20 10:44:19.397 Test[7536:12871658] Insertions: 1 deleteions:2 modifications:0
2017-01-20 10:44:19.397 Test[7536:12871658] Insertions: 1 deleteions:2 modifications:0
2017-01-20 10:44:19.398 Test[7536:12871658] Insertions: 0 deleteions:1 modifications:0
2017-01-20 10:44:19.402 Test[7536:12871658] Insertions: 0 deleteions:1 modifications:0

_nfA = [[[ModelA allObjects] sortedResultsUsingKeyPath:@"pk" ascending:NO] addNotificationBlock:...