Black-tailed Godwit 1S-2W

Black-tailed Godwit, in moult to Non-breeding.

Since there're not much breeding plumage, it probably in moult to 2nd Non-breeding.

 I think adult bird should have more breeding plumage in this stage.

Black and Bar -tailed Godwit

Size comparison of 2 Godwits.
Black-tailed Godwit on left, Bar-tailed Godwit on right.

 Black-tailed Godwit.  Moult to non-breeding.