complex habit scheduling in orgmode

Question

There are a few complex habits/tasks that I wish orgmode to handle, and I'm not quite sure how to program them:

• A habit that has to be done twice a day, between certain hours (E.g. 8-9 and 18-19).
• A habit that has to be done over the weekend (Between Thursday-Saturday).
• A task that occurs every 6 months, twice a day between certain hours, for a duration of 21 days total.

Can someone help with adding the right SCHEDULE?

Answer 1

• Weekend only habit:

  SCHEDULED: <2013-12-13 Fri ++1w/2d>

  This will cause it to repeat every Friday (regardless of when completed), and will be late if delayed by more than 2 days after the next notification.

• Twice a day habit:

  This will most likely have to be created as two separate habits, one for the first timeframe and one for the second.

• Bi-annual:

  Most likely requires two TODO's as well to allow for the two timeframes. I'm not sure if there's any real way of doing so without using complex diary SEXPs which you would have to create every 6 months (or update the SEXP to match the next 6 month span). Org TODOs/Habits don't usually include an 'end-date' when they repeat.