Photo 3: LBBG intermedius sub-adult, January 05, 2001, Westkapelle, the Netherlands.

Another 5cy bird, assumed to be of the race intermedius. This one is more robust with new dark slaty grey upper parts, glancing in the sun. The primaries have relatively small white tips and are not typically adult-like (although one has to be careful to use this characteristic in ageing LBBG, since some intermedius populations might well develop only small white tips in adult freshly moulted primaries, keeping a sub-adult look).
P10 shows a large white mirror, the bill is yellow but with a hint of dark bill-band. Red on the gonydeal angle is well visible.
The iris and legs are pretty adult-like already.

Small white tips at fresh primaries do not necessarily point to sub-adultness and ageing LBBG may best be based on a combination of features, like: 

• presence of a bill-band (or dark markings on the bill);

• pale yellow iris with a bluish wash;

• clear sub-adult feathers in the wing coverts or primary coverts;

• black markings in the tail;

• small primary tips and a reduced mirror on P10 (the borders of the mirror hardly reaching the edge of the inner and outer web of the primary).

Especially argentatus from northern Scandinavia (Norwegian Finnmark) with either yellow legs or pink legs, seem to keep some black at the bill in its adult plumage. It's interesting to see whether this also applies to intermedius LBBG and maybe ring recoveries can unveil this in the near future. It being the case, both bare part coloration and primary tip pattern on its own may no longer be reliable diagnostic features for separating adult intermedius from fourth winter (5cy, with completely moulted primaries).