Photo 3: LBBG sub-adult?, June 16 2001, Missouriweg Maasvlakte, the Netherlands. 

Many 4cy LBBGs show a combination of small tips and a mirror on p10. This mirror is relatively small in most cases, often not reaching the primary inner-edge.

This is a sub-adult bird, resembling an adult in upper-parts. The jet-black primaries show only small white tips and a small white mirror on p10. The p9 mirror is lacking. The tail in 4cy LBBG may show some isolated black spots and often the bill has a faint black mark on the upper mandible.
Note the bare area around the eye; head moult has started.