Grey geese over Deer Park

I saw 4 large grey geese flying (pretty slowly, obviously) North into the wind over the Deer Park this morning at about 1030. They appeared relatively plain and uniformly coloured overall, and certainly compared to the Canadas that regularly commute between Skomer and Marloes Mere, with noticeably dark heads and contrasting paler necks and what appeared, at range, to be dark bills. The 4 birds were of two different sizes: two were very large (close to Canadas in appearence), the others distinctly smaller, but still substantially larger than, say, Brents. The necks were all distinctly long and thin (initially in silhouette and at distance I thought that they were swans), and the heads and bills pretty delicate (i.e. not the massive, chunky, look of a Greylag). The bodies looked heavy and the wings long.
Based upon their size and colouring my guess is that these could have been Bean Geese: given the slow pace they were making against the wind it might be well worth checking likely staging areas further up the coast.