Hello jamesin1980,
Great question! You certainly can make advance payments, however we don't have that feature on our website quite yet. We know there are many things missing and our design teams are working to add more features slowly. You can call us at 1-866-347-3262 to make an advance payment at any time, or schedule payments to debit at a future time. Let me know if you have any questions.
Thanks,
Amanda