It's interesting to note the bright yellowish leg colour shown by this individual. Although wintering birds of the race curonicus (the northern migratory form) should show dull pinkish-grey legs, it appears that first-winter birds of this form, as this bird is, in the east of the range of curonicus, regularly show much brighter legs than those wintering in Africa. Wintering first-winter birds in India also show bright yellow/orange legs, as do vagrant LRPs reaching Australia.
Other pics of curonicus LRP on this site also show this feature, some with even brighter legs.
Not sure what the leg colour of first winter jerdoni is, as the only photos I've found on this site are of adults in April.
Incidentally, the Avifauna is unclear about which race breeds in HK. However, adults breeding in HK do appear to show the characters associated with jerdoni. If someone could photograph LRP at the nest in HK, this could be easily clarified.