Please head over to the "Subscriptions" section of your account with us at www.drinksoma.com/profile (the login is at the top right corner of our homepage).
If, say, you're traveling for a bit -- or you need a filter sooner than you thought -- you can use the "Reschedule" feature to customize when your next filter comes. Your normal 60-day interval will re-set after that filter ships out.
At this time we only offer a filter delivery frequency of two months. If you might need filters more frequently than once every 60 days, you can always purchase an extra, standalone filter subscription over at www.drinksoma.com/filters.