How many submissions can I receive from customers with a JotForm?

From reading the pricing plan it says the limit is 500 total submission storage for a free account on JotForm, can submissions be deleted once they have been received and actioned or will they permanently be stored?

Monthly Submissions and Total Submissions Storage limits are different from each other. Free accounts are limited to 100 Monthly Submissions and 500 Total Submissions Storage. 

The total submissions storage is a fixed limit and this means that you can only store up to 500 submissions total. Your older submissions will be automatically deleted once you hit the limit, they are not stored unless you'll upgrade your account to our Storage Plan or to our regular plans such as the Bronze to have an unlimited Total Submissions Storage.