If you wish to change your plan type, either to upgrade to a more expansive plan, or vice versa you can easily do it through Manage Subscriptions under your Settings tab by following the below steps.
1. Click on Change Plan
2. Select the plan of your choice
3. Confirm your details and subscribe with PayPal. If you have a discount code it will automatically be applied to the new subscription.
When you upgrade, your account will immediately be associated with the new plan and its features. You will only be charged the difference between the two plans, based on the number of days remaining in your original subscription.