For a monthly subscription in PayPal Pro, when does the first payment come out?

I have a form where users are paying for a trip in two monthly installments.  When does the first installment get paid from the user's PayPal account?  Is it as soon as they submit the form and the second payment comes 30 days later?

The first subscription payment will be immediate unless you set a trial period.  You can also set a larger amount for the first payment if you need to include setup fees or anything of that nature.

For more information on setting up subscriptions, please see the following guide:

https://www.jotform.com/help/166-How-to-Setup-a-Recurring-Payment-Option