(2 images) Larus fuscus fuscus 3cy C3XA, July 09-11 2003, Tampere, Finland (61.33N 24.59E).

C3XA was ringed in Pälkän, Finland; ringed as pullus on June 28 2001 by Risto Juvaste.
Recorded at Tampere:
2003-06-14, 2003-06-15, 2003-06-17, 2003-06-18, 2003-06-20, 2003-06-22, 2003-06-28, 2003-06-29, 2003-07-02, 2003-07-05, 2003-07-06, 2003-07-09, 2003-07-11.

Larus fuscus fuscus in 2cy often returns with completely replaced primaries and secondaries. In 3cy, fuscus more often shows a clear division between fresh inner primaries and older outer primaries, the inner primaries often showing neat white tips and the outer primaries often second generation-like with rounded tips and paler bleached brown. The arrested moult in the primaries is often reflected in the secondaries and (to a less extend) in the tail-feathers as well. The older tail-feathers (often R5 is older) still show a broad dark sub-terminal band.
3cy fuscus often have some black markings on the bill, which is otherwise much adult-like, with a clear red gonydeal spot. The colour of the naked parts are adult-like as well. 
The scapulars in 3cy are often completely adult-like, lacking internal patterns; plain blackish grey with a mahogany hue on the older feathers. Most wing-coverts and tertials are adult-like blackish grey as well, but often 3cy birds show some very bleached pale brown wing-coverts, normally in the greater covert bar and in the upper rows of the lesser coverts. These bleached wing-coverts accentuate the jumpy sequence in the last wing-covert moult cycles, as there is often no clear pattern in location of these bleached feathers. Head and body feathers normally are snow-white by July.

C3XA was ringed in Finland, now in 3cy. This 3cy fuscus has arrested primary moult prior to northbound migration: there is a clear division in the visible outer primaries between P8 and P9. The two outer primaries (P9-P10) are bleached brown and P10 is lacking a mirror. These abraded primaries are probably retained 2nd generation flight feathers. The other visible primaries, P5-P8, are much darker with small white tips, probably 3rd generation feathers.
Note the fresh rectrices, they appear all white and note the limited dark markings on the bill and the retained bleached wing-coverts, typical for 3cy birds.