If you fly a trip from stby, you are guaranteed (I believe) one local day off, before being liable once again for stby. At least once in your block, you will be allocated a long break (minimum 2 days off) Can't recall if this could happen down route!
He's right. After a trip, you get one local day (night) off before you can be allocated another trip. You can volunteer to reduce this (for which you will receive a payment) in order to do a back to back trip. The 'long break' must be notified
in advance and must be taken at home. However, the company can take into account days off down route for their planning, although this is not usually of great significance on the 777 as the trips are generally pretty short.
Tandemrotor,
Are you coming back down south or staying up north?