I don't know where the focus is nor what the subject is with this photo. Despite the title, I only see 2 dots that look vaguely like birds. The tree does nothing except confuse the viewer on the subject. There's a fair amount of noise in the sky and the light is really nothing great. Overall, it just looks like an accidental test shot that got submitted by mistake. Challenge-wise, it's way off. If you really wanted to show "busy" birds flying, capturing a whole flock would be better. If not possible, another idea would probably be better but only you can think of that. Sorry if this sounds harsh but it's meant to help as this was the lowest score I've given so far in this challenge.
You've probably already heard this, but it is really hard to see the birds in such a small picture. Have you looked into Paint Shop Pro? The tree appears out of focus, but I like the clouds.
those birds certainly are busy flying so this meets the challenge, the image itself is a little small in my opinion and I feel the tree top and birds are a little too far away, the use of the thin black border was a very good decision and the overcast sky was a good choice for this composition :)