Harry and his surviving friends after the war discover the deceit Dumbledore had done and caused the death and wrongful imprisonment of many, especially when Harry was thrown into Azkaban due to his final will that he left for the Ministry of Magic. Harry had quickly learned that the Dementors never went after him anymore and he can communicate with them, most of the time he would be given messages from Death by them about how he is setting up a plan to get Harry and his friends a way to reverse what Dumbledore had done. Eventually, they would all be sent to Voldemort's past when he was at Hogwarts as a student.