Also anyone who has used this site can they help us to understand what they mean when they say the ticket is valid from the time of issue not date of departure. Does this mean we will have to wait till just a few months before we leave?
It means exactly what it says. Certain tickets are valid for 12 months from the date of departure and others are valid for 12 months from the date they are issued. So if you are buying one that is valid for 12 months from the date of issue well that is going to mean you'll need to wait until very close until the time of departure to purchase if you don't plan on using it for nearly 12 months.