Our Part A says the same about days off. I never do anything related to work on a day off. I've missed many deadlines for 'stupid online course whatever' or 'how to lift up a box'.
I've received several management calls indicating that I must complete these in my own time however, when I ask for that in writing it goes very quiet at the other end of the line.
Mind you I work in the UK not HK, still...
'em.