Help ID my mutt!

The rescue had her listed as Australian Cattle Dog/Lab mix (they just guess).
Now that she is getting older she is way to small to even have lab in her, and we definitely doubt the lab part.
I have no doubt she has the cattle dog in her, but can't seem to place what else.
Maybe border collie, maybe a terrior of some sort?
She is 6 months old, 35 lbs.

She's a mongrel.

Could be some collie in there.