I first saw the birds from 150 yards. I knew I had to close the gap. As I did and before I got close, they flushed and went north. In a little while I drove north and was delighted to see the had landed. I approached from the north so I could get the best light for photos. 

When I got within 60 feet I put the scope on them. They looked in shape much like a Bairds, where the wing tips exceed the length of the tail. I would estimate about 7 inches long. Bill is short and straight much like a Bairds with very slight decurve, legs dark like Bairds. But the very splotchy heavily spotted appearance of the breast was very different than the Bairds. In addition, dark streaks went down the flanks and sides of the birds. Breast and belly otherwise white. Back, head were mottled black spotting on browinh base. 

A quick look at the book showed they were all breeding plumage adults. 

I flushed them by accident and took some quick photos. The rump was pure white. It did not have the central dark stripe down the rump like Bairds would. 

I have been keeping bird notes for 40 years. I have documented many WRSA over the years and predictably the bulk of them come through in late May and early June. These are right on track.