There was an ongoing campaign by many people including ex-soldiers for their release. He both shows dominance with this and also tries to calm down the
ex-military men. This comes in a time where Selahattin Demirtas (APO the Second) was given 42 years of prison. I think Erdogan is showing gestures of reconciliation with some influential actors in the State after the weak results in the election and the coming end of his political career. A certain atmosphere is created including the rebalance in circles connected to the organized crime.
The circles in organized crime have seriously damaged the institutions of the state as much as AKP has