I agree with everything marbles has to say as far as time off is concerned. Many people seem to prefer to NOT have their family with them for the first few weeks of ground school, although this is a personal preference of course.
With regard to ID90 ticketing, you are only entitled to CX discounted flights between domicile and HK during your first 6 months. Note that you do NOT have interline rights for this time – in other words CX is the only carrier you can use. The rule applies to both you and your family however, so if you wife / kids come over early, you can fly them home ID90. As an admin point, ID90 tickets purchased in the first 6 months have to be paid ‘up front’. If you do not use the ticket however you can claim the full amount back.
Fleet manager approval depends on which fleet you are with, and at what stage of training you are. Once you are on the line, it’s normally your responsibility to be in the right place at the right time, and adequately rested.