[0] Advance VAT Invoice Electronic version: available for download in your account within 48 hours after we receive your payment. Hard copy: sent to your postal address once the electronic version is generated. Note that postal delivery can take up to 10 business days Request duplicate hard copies for previous payments in your account on the Transaction history page. To get there, click the gear icon and choose Billing. Requests must be made only after 10 business days have passed since the payment appeared in your account. [What it is] 
Generated for each payment you make for the day the payment was received, this document states the full amount of payment (including VAT). The document number starts with "A".