Not ready for prime time.
American redstart, Rondeau Provincial Park, June 2, 2023.
Looks like a young male growing into breeding plumage.
Young male American Redstarts have gray-and-yellow plumage, like females, until their second fall. Yearling males sing vigorously in the attempt to hold territories and attract mates. Some succeed, but most do not breed successfully until the following year when they develop black-and-orange breeding plumage.