Going from paid back to free

I have been using the paid version of JotForm at $9.95 for several months and am wondering if I can go back to the free version without any impact on my existing forms?  My form is for something intermittent where a bunch of people submit at certain times of the year, and other times are quite low in the number of submissions.  Can I go back to paid and then back to free throughout the year, or do I have to stay at one level or another?  Thanks for your help!