what breed do you think my dog is?

by zara
(new zealand)

This is Kira he is now one years old, ive had him since he was six weeks old. I need help figuring out what breeds he may be mixed with. I got told he was Red Heeler/Australian Cattle dog and border collie. But his coat makes me think otherwise... He had brown/orange/white patches when he was a small puppy but now he has a more consistent white and orange coat. Hes medium sized and has a lean/slim build. Any help would be lovely. Thanks :)