We sent invoices the first of each month with the usage from the month before. We don't invoice in advance but only afterwards.
Invoices will be sent to your account email address, if you wish to receive your invoices on a different email you can contact support so we can arrange that for you.
Can I pay annually?
In short: no you can't. Because we have no contracts and want to give all of our customers the freedom upgrade, downgrade or cancel anytime they want we keep invoicing on a monthly basis. When we should do annually payments we need to make a new invoice or credit payment each time a customer upgrades or downgrades.