Good Dalek Incident

The Good Dalek Incident was the Time Lord designation for the event in which the Twelfth Doctor met Rusty, a Dalek who defected to the Combined Galactic Resistance. (TV: Into the Dalek, PROSE: Dalek Combat Training Manual)

Dating
According to the research of human historians, Rusty fought towards the end of the Dalek Wars. (PROSE:  The Astounding Untold History of the Greatest Enemies of the Universe) Alternatively, 21st century alientologist Justin Richards stated in his book The Secret Lives of Monsters that the events surrounding the Aristotle occurred at "the height" of the Dalek Wars. (PROSE: The Secret Lives of Monsters) Another historical account however held that the Combined Galactic Resistance against whom Rusty fought had operated during the Great War. (PROSE: The Whoniverse)

However, Rusty also had access to memories of post-Last Great Time War events, suggesting he was from a later point in Dalek history. (TV: Into the Dalek) Indeed, Time Lord research placed Rusty's existence after the War. In fact, the Lords of Time stated the Dalek unit existed at some point after the Siege of Trenzalore, (PROSE: Dalek Combat Training Manual) which the human historians had tentatively dubbed the destruction of the Dalek species. (PROSE:  The Astounding Untold History of the Greatest Enemies of the Universe)

Aftermath
According to human historians, Rusty's betrayal sent the Supreme Council in a world of worry, but their experiments proved that his freak turn of heart could not be mass-replicated. Relieved, and unwilling to snuff out such beautiful hatred as Rusty's, they consigned him to the Dalek Asylum, home to Daleks whose hatred was so powerful it threatened their own kind in one way or another. (PROSE:  The Astounding Untold History of the Greatest Enemies of the Universe) The asylum was ultimately destroyed by the Parliament of the Daleks. (TV: Asylum of the Daleks) Alternatively, the Time Lords believed Rusty to be from a later point in Dalek history, dating his crusade against the Daleks beginning sometime after the asylum's destruction. (PROSE: Dalek Combat Training Manual)