Gulls - Attenborough, UK (today) (1 Viewer)

I've tried ID'ing these with my reference guide - but I'm not really getting anywhere...

1. Herring gull, Immature???
2. Lesser-black-back, Adult [Red gape, red eye ring]
3. Lesser-black-back, Immature??? [...wrong colour legs]
4. Common gull
5. Black headed gull still in moult??? [

Any help appreciated.

1 & 3 both look like 1st calendar year Herring Gulls (both show, for example, traces of pale 'window' on the inner primaries, though it is hard to see due to the angle in pic 1, and the partially folded wing in pic 3.
2 adult LBBGull (leg colour normal yellow)
4 adult Common Gull
5 adult Black-headed Gull starting to acquire breeding plumage (I deliberately didn't say summer plumage!). Quite a few birds I've seen in the last couple of weeks already have full hoods, but it is still quite early and majority are still in 'winter' (non-breeding) plumage.

Thanks so much for the IDs and info SteveClifton!