According to a report from Edmund on Wednesday afternoon, the Saints were unprepared to offer the South Australian a contract for next season, despite his surprising return to form in the back half of the season.
After returning to Brett Ratten's senior side in Round 11 against North Melbourne, the 26-year-old played 11-straight games in a red, white and black guernsey and found the football at an average of 26.1 times per contest.
Although his numbers were much improved from those that he had amassed across his previous seven seasons in the league, the knock on Dunstan's game has been his perennial ability to turn the ball over.
Many were surprised that he was dropped from Ratten's starting-22 for the club's final fixture against Fremantle in Hobart last Saturday, but having recorded a season high eight-clangers against the Cats the week prior, his exit papers appeared stamped after his side's loss.
As reported by Edmund, Dunstan will almost certainly attract attention from rival clubs - including the pair that hail from his home state - and his signature should be easy to obtain given he will enter the off-season as a delisted free-agent.
Dunstan will exit the four-walls at Linton Street after playing 116-games for the club that drafted him with the 18th pick of the 2013 draft.