An Airbus SOs roster is dependant upon whether you are 340 and 330 qualified or solely 340.
340 only (your first 18mths) is identical to the 744 SOs
If your 330 & 340 then expect 1 extra trip (either to Australia, where you work both directions or to the Middle East, where you generally work over and pax home)
As an SO I averaged 19days off per month (6-8 sectors)
As a JFO I average 13days off per month (14-28 sectors)
As and FO I average 17days off per month (6-14 sectors)