Tickets are sold in groups. The more you purchase the cheaper they are. Once you have them in your account, you can use them at any time, on any service with any frequency. They do not expire. If you decide that you would like to permanently cease using the service, we return 90% of the value left in your account at the time. In this way, you can get the cheap price, but not have to travel 10 times a week (in and out) to get the value of the discount.