I saw these two different birds about a week ago in Western Estonia. Seems like Long-tailed Skuas are having sort of influx after good breeding year and i thought that these birds fill the criteria of juv LT Skua. Problem is, that it's still a very rare bird in Baltic Sea and i don't have any experience with juveniles. And Arctic Skua is a uncommon migrant here as well (max 10 birds in good days) so there's no chance of good Skua-training here. Anyway these bird looked very elegant and light in the field. Photoshop wizardry didn't help much though, nothing diagnostic can be seen really. And the jizz of the birds changes in different shots pretty much.