Your ticket is valid for 24 months. On average, our passengers have to sign up for 2/3 flights before they actually fly as our flights are 100% dependent on safe weather conditions. Sometimes, they fly on the 1st flight they signed up for, but sometimes, it takes 3 or even 4 times before they fly.
The moment your flight gets cancelled, your booking code becomes active again and you may sign up for another flight.