What is the difference between available space and storage?

The Bronze plan offers 10GB of space with unlimited storage.  What does this mean?

Bronze subscription plan provides 1000 monthly submissions, and 10 GB available space.

The 1000 monthly submissions refer to the number of submissions the user can accept for the whole month, regardless to the number of forms used. So as long as a form in the account receives a submission, it will be counted as 1, from the 1000  that is allotted. The counts you receive refresh every month. So even if you have received 950 submissions today, it will restart to zero starting the next month. It also does not matter whether the submission you have received has a file uploaded with it (note: there's a different counter for file uploads)

Regarding File submissions

Bronze is allowed to use 10 GB of storage space for file submissions. This counter does not restart every month unlike the submission counts. The storage space or uploads counter will stay as long as you do not delete the submission in your form.  You may also set to receive file submissions of any file types and/or set limits on the size of the file to be uploaded to be uploaded.

I hope this clears out some concerns. If you need further assistance, feel free to revert back.

Thanks.