If you downgrade your plan to Free, your card on file will not be charged again. If you downgrade your plan to another paid plan, your card on file will be charged the new amount and you may receive credit that will be applied to future Selz invoices. For details on App & Plan Billing, log into your Selz account, then click on Settings > Billing. Please also note that if you have a paid account with another service (like MailChimp or AWeber) simply removing the app will not affect your recurring payments to that other service.
For more details, see our Terms.