When you are on a monthly or annual billing cycle, your credits will revert to the allotted monthly credit limit per month, and they reset to the amount shown on our pricing page for each month:
Pro Monthly/Annual - 1,000 credits per month
Studio Monthly/Annual - 4,000 credits per month
Therefore, in a billing month if you're on a Pro monthly or annual plan, let's say you use only 400 credits. Then, you have 600 credits leftover for that month.
On the next first of the month from when your billing started (e.g., you sign up September 5th, your next billing month is October 5th), your credits will re-up back to 1000 credits, since that is the monthly credit limit we advertise on our website. You do not get a full 1000 credits added because you already had the 600 credits from before, therefore, 400 is added the next month to put you back to 1000 credits for the month. As a reminder, credits do not rollover from month to month.