I found two Buff-Breasted Sandpiper today on the Mudflats at the Brilyea Access today (8/29). I also saw one yesterday, but failed to identify it.
Another highlight was a lone Stilt Sandpiper. Both species life birds for me.
The best location to look at the shorebirds now is on the trail from the second parking lot. If you go down it about 2/3 of a mile, you will see an open field on your right filled with Goldenrod. At the southern corner of that field you will find a path that takes you down to several openings from which you can view the mudflats. In that area I saw over 300 shorebirds spread over a football field sized mudflat. Mostly Semipalmated and Least Sandpiper, But also Killdeer, Greater and Lesser Yellowlegs, Semipalmated Plover and a good probability of other hidden treasures mixed in with them.