JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
You are free to download all your data at once, forms, submissions and uploaded files, here is a guide that will help you to export all this data at once: How-to-export-all-of-your-data-at-once
If you decide to upgrade only form one month then if you receive a lot of uploads, when you downgrade to free you will alerted about over-quota, so you will need to delete your submissions where you received uploads in order to get free space.
To avoid loosing data you should follow the guide provided above so you will save all your received data.