You have the power to upgrade your plan at any time in our billing and support system at http://www.mddhosting.com/support. To upgrade your plan you would simply need to log in and then go to "My Services". Once you see your hosting plans you will click the white page with a green arrow () next to the plan that you wish to upgrade. On the next page you will click the "Upgrade/Downgrade Package".
When you upgrade your plan a pro-rated invoice will be generated for the difference between your old plan and the new plan until the end of your current billing cycle and as long as you are transferring to the same type of hosting (such as from basic shared to intermediate shared) the change will happen immediately as soon as the invoice is paid.
If you are upgrading to a different type of hosting account such as from a basic shared hosting plan to a basic semi-dedicated hosting plan the process will be the same except for that the upgrade will not happen automatically. We will handle transferring your account from the old server to the new one and you will not incur any downtime or experience any issues in most cases. If you have any questions about this at all please contact the Sales department.