Instead of only being resurrected, Jason’s body regresses to the age of 12 as he digs his way out of the coffin. Being alive, but with no coherent memories of the last three years, Jason takes up life as a street kid once again.
Seven years later, Damian Wayne stumbles across Jason (now going by Alfred Todd).
Timeline without important spoilers: (Important reveals for the plot are not included.)
~ Everything is the same as the comics until Jason dies.
~ Jason is revived and “rewound” back to being 12 years old.
~ Tim becomes Robin (I’m making Tim 11 at this time).
~ Jason lives on the streets for 6 years.
~ Damian comes to Gotham.
~ Bruce “dies.”
~ Dick becomes Batman and Damian becomes Robin.
~ Jason starts picking up street kids and taking care of them.
~ Jason finds Sasha after she smothers her father and offers her a place at the apartment.
~ Bruce returns. Dick becomes Nightwing, Tim becomes Red Robin, Damian stays Robin
~ Jason breaks into a warehouse thinking a child has been kidnapped and runs into Damian for the first time.