Tickets for the hotly anticipated event went on sale at Aberdeen Box Office at 10am today to APA Friends, and sold out within 20 minutes.
All bookers will now have the opportunity to pick up the remaining tickets when the event goes on sale to the public on Friday 13 September at 10am.
After announcing his retirement as manager of Manchester United after 27 years, Sir Alex went out in a blaze of glory, as his team won the Premier League for the 13th time.
His autobiography will be published on October 24 and he will undertake talking engagements in Manchester, Glasgow, Aberdeen and Dublin.
Sir Alex has been reflecting on and jotting down the highlights of his quite extraordinary career for the last four years and it is a story that promises to reveal, entertain and inspire.