What period of time is the 100 limit based upon?

I am the webmaster for a non-profit organization that uses your forms for adoption agreements for pets needing homes. We just started using your service. What period of time is the 100 limit based upon...the calendar month or the 30 day period based on the date we created the account? Also, what happens if we exceed 100 during a month? Do the submissions automatically get blocked or do we get some sort of heads up about upgrading? Thanks.

It's the calendar month. The Submissions Counter will reset on every first day of the month, 00 EST. 

When you reached your limits, your forms will be temporarily disabled until the next reset schedule or until you will upgrade your account to our next plan. No one can submit to the form when it's disabled.

Yes, you will get an email from us when 90 percent of your submission is already consumed. 

Thanks