Once your month is up, when you log in you will be directed to the purchase page to renew. At that moment you can decide whether you want to pay more or not. And of course you can always buy an extra month later and continue your program whenever you want. Your right to access and use the content expires as soon as the period you paid for has ended. You can buy an additional month at any time to continue the program where you left off last time. This is even possible after a few months or years break. You choose how much you want at any given time.