Drafts and scheduled posts, and failed ones (409 post_not_editable otherwise). A failed post, or the failed accounts of a partial one, is sent again after the change: now, or at a future scheduled_at (failed posts only; 400 schedule_not_allowed for a partial one). Only failed accounts can be changed there; the accounts already published keep their text and media. 409 post_partly_published: part of that account's post already went out (a thread), so it is continued with POST /v1/posts/{id}/retry instead. targets[] changes the accounts already in the post: a field sent replaces that account’s (options as a whole), content or media_ids null makes it follow the post again, a field left out stays. Accounts cannot be added or removed (400 account_not_in_post). Requires the write scope.