You actually can't exceed your disk quota, since our systems will prevent you from doing so. When you've reached your disk space limit no further uploads will be permitted. Make sure to always leave a minimum of 5 Mb of available disk space on your account or else emails being sent to you will start bouncing back.
You can remove your disk space limitation at any time by upgrading your hosting package or ordering more disk space. See our hosting add-ons for pricing. Additionally, our system will attempt to contact you via email* when your disk space is at critical status (90% full) and when your disk space is full.
*You will be emailed at the address used when you signed up for hosting which should always be different from any of your domain accounts.