UIView transitionWithView: animation behavior with background color

I created a simple project to experiment with a piece of animation UIView transitionWithView:

and ran into some rather strange behavior.

The animation only works as intended with the label text (changes it while viewing it halfway through), but the color change happens at the end of the animation, yes. Is there a way to use this kind of animation to change the background colors (images?) Halfway through the animation? I can create something similar to myself with Core Animation, but I don't want to reinvent the wheel. I feel like I just am not using this method correctly

The whole example code:

#import "ViewController.h"

@interface ViewController ()
@property (weak, nonatomic) IBOutlet UIView *containerView;
@property (weak, nonatomic) IBOutlet UIView *innerView;
@property (weak, nonatomic) IBOutlet UILabel *label;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    self.innerView.layer.cornerRadius = 25.0;
    // Do any additional setup after loading the view, typically from a nib.
}

- (UIColor *)randomColor {

    CGFloat hue = ( arc4random() % 256 / 256.0 );  
    CGFloat saturation = ( arc4random() % 128 / 256.0 ) + 0.5;  
    CGFloat brightness = ( arc4random() % 128 / 256.0 ) + 0.5;  
    UIColor *color = [UIColor colorWithHue:hue saturation:saturation brightness:brightness alpha:1];

    return color;
}


- (IBAction)flipAction:(id)sender {

    static int i = 0;
    i++;

    [UIView transitionWithView:self.containerView
                      duration:0.5
                       options:UIViewAnimationOptionTransitionFlipFromTop
                    animations:^{

                        self.innerView.backgroundColor = [self randomColor];
                        self.label.text = [NSString stringWithFormat:@"Flip - %d", i];

                    } completion:nil];

}

@end

      

        
        
        
      

    

Sidenote. Interestingly, I found that when the animation parameters are set to UIViewAnimationOptionTransitionCrossDissolve

, it does the same thing, but! if you set it to 0 it will animate the color property by duration. Pretty sure that in this case we see an implicit animation of the layer