Are there any flight images of the first two birds? While I agree that the head patterns do seem more like that of a non-breeding Franklin's Gull, there are some features that give me cause for concern, including the lack of pale fringes to the innermost visible primaries at least, the bill length not seeming short enough for Franklin's (the foreshortened bill in the second image especially looks as though it would be long), the dirty smudgy grey tones on the nape and, to a lesser extent, the flanks on both birds, the worn juvenile coverts on the second bird, and I wonder if they may just be 1st cycle Laughing Gulls attaining a partial hood?