Can you have a temporary paid account when needed?

Hello, we have an account for a school which uses forms only occasionally and usually the free account is sufficient. From time to time we need one that will take over 100 submissions, and so we need to sign up for a higher account. 

Is it possible that we can sign up for only a month or two as needed and then go back to the free version until the next time we need more submissions without losing the account entirely?

Thanks for your help!

Yes, it's possible to purchase a subscription for one (or the needed) month only then you will need to request the downgrade right before the renewal date so you are not charged again, the guides below will help you doing so: 

https://www.jotform.com/help/331-How-to-Upgrade-My-Account

https://www.jotform.com/help/341-How-to-Downgrade-Subscription-Back-to-Free-Account

Now, please note that free accounts are limited to store the newest 500 submissions only so you may download your data to have a copy of all the submissions you receive: 

https://www.jotform.com/help/374-How-to-Export-All-of-Your-Data-at-Once

https://www.jotform.com/help/73-How-to-Download-Form-Submissions-as-Excel-CSV-PDF

Also, deleted submissions due to the storage limit will be recovered when you upgrade. 

I hope this helps.