You need to make an upfront payment. Initially, we collaborate with you to estimate the number of employees who will participate in the current month. In the following month, you'll be billed for the actual number of participants from the previous month, accounting for any differences between your prior payments and any outstanding debts on either side (ours or yours).
For instance, if you decide to launch Random Coffee on the 15th of January and we mutually agree that 100 employees will participate, you will be charged for those 100 users. Then, on the 15th of February, we discover that 120 users participated. Consequently, you'll be billed for 120 users for the upcoming month, as it's reasonable to assume a similar number of participants next month compared to the previous month. Additionally, you'll be billed for the 20 users who participated in the previous month but hadn't been accounted for in your previous payments.