Send Invitation Well in Advance. Some people send graduation announcements that double as an invitation to the ceremony or to a post-ceremony gathering. In this case, the recipient should receive the mail no fewer than two weeks before the date of the event.As such, the time at which you send the announcement depends on the speed of the mail system and the distance to the recipient.The rule of thumb is to send the announcement/invitation four to six weeks before the event.s such, the time at which you send the announcement depends on the speed of the mail system and the distance to the recipient. The rule of thumb is to send the announcement/invitation four to six weeks before the event.