The Contract only allows you to chose your time on/off if you opt for the Worldwide option which carries a lower daily fee than the fixed four weeks on and two off and generally has a minimum time on base of 3 weeks.
On the 4/2 there is a yearly holiday allowance of 30 days (unpaid) and is by request.
The only exception is those who have a FIA contract (Icelandic pilots union), mainly Icelandic nationals and they operate 21/21.
All Accommodation, travel and transport costs are covered and arranged by AAI.