Adjustment invoice
TL;DRA new invoice for the extra amount a mid-period change adds, issued beside the original.
When an upgrade lands after the period's invoice has already been sent, the additional charge cannot go on that document. It becomes an adjustment invoice covering only the difference from the change date to the period end.
Draft invoices, by contrast, are edited directly — the fork is whether the original was still open.
Where it happens in Sonic
Next
See it on your contracts
A walkthrough on the agreements and files you actually bill from — not a slide deck.