Curlew or Whimbrel?

This pic was taken last Sat at RSPB Arne on south coast and was at a great distance so the pic is heavily cropped already. Even with bins not sure of ID, there were a lot of curlew about but this one seemed smaller, less upright with a darker slightly more curved bill possibly shorter. There were no Godwits about to compare with either.

KR
Tony

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