This is going off of DC's established dc continuity, and im really only saying headcanon, because it's my opinion on what the dc comics continuity looks like right now:

Wonder Woman debuts: Aug 1939 JSA form: Nov 1940 JSA disband: Oct 1951 Diana returns to Themyscira: Oct 1951 Superman debuts: Jun 2011 Batman debuts: 2011 Aquaman debuts: 2011 Green Arrow debuts: 2011 Wonder Woman returns from Themyscira: 2011 The Flash debuts: Oct 2011 Hal Jordan debuts: Dec 2011 Supergirl debuts: May 2012 Robin debuts: May 2012 JLA form: July 2012 Flash of Two Worlds: 2012 JSA reform: 2012 Doom Patrol form: 2012 Teen Titans form: Apr 2013 Batgirl debuts: Nov 2014 Guy Gardner debuts: 2014 Barry and Iris marry: Nov 2014 Doom Patrol die: 2014 Green Lantern/Green Arrow: 2015 Black Lightning debuts: 2015 Iris west dies: 2015 New Teen Titans form: 2016 Jason Todd debuts: 2016 Outsiders form: 2016 Infinity Inc form: 2016 Judas Contract: 2016 Ted Kord debuts: 2016 Question debuts: 2016 Trial of the Flash: 2016 Crisis on Infinite Earths: July 2016 Shazam debuts: 2017 Legends: 2017 Jl International form: 2017 The Killing Joke: 2017 Jason Todd is killed: Apr 2017 Invasion!: 2017 Tim Drake debuts: Jan 2018 War of the Gods: 2018 Armageddon 2001: 2018 The Death of Superman: Nov 2018 Return of Barry Allen: Jan 2019 Superman returns: 2019 Knightfall begins: 2019 Emerald Twilight: 2019 Impulse debuts: 2019 Zero Hour: 2019 Knightfall ends (KnightsEnd): 2019 Green Arrow killed: 2019 Birds of Prey formed: 2019 Underworld Unleashed: 2019 Lois and Clark marry: 2019 Contagion: 2019 Final Night: 2019 JLA reform: 2019 Cataclsym: Dec 2019 Young Justice form: 2020 Jon Kent born: 2020 (ages up to 7) Day of Judgement: 2020 Cassie becomes Wonder Girl: 2020 No Man's Land: Mar-Dec 2020 Wally and Linda marry: 2020 Titans form: 2020 Stargirl debuts: 2021 JSA reform again: 2021 Our Worlds at War: 2021 Green Arrow Quiver: 2021 Joker's Last Laugh: 2021 Whatever happened to truth, justice & the american way: 2021 Hush: 2021 Sub-Diego: 2021 Graduation Day: 2021 Huntress joins Birds of Prey: 2021 Teen Titans reform: 2021 JSA -Black Reign: 2021 Superman/Batman Public Enemy: 2021 Identity Crisis: Mar 2021 GL Rebirth: 2021 Ted Kord killed: 2021 Under the Red Hood: 2021 Infinite Crisis: May 2021 52: May 2021-May 2022 One Year Later event: May 2022 Damian Wayne debuts: 2022 Amazons Attack: 2022 Sinestro Corps War: 2022 Ollie and Dinah marry: 2022 Superman Brainaic: 2022 Batman R.I.P.: 2022 New Krypton: 2022 Final Crisis: 2022 Battle for the Cowl: 2022 Batman & Robin debut Cry for Justice: 2022 Blackest Night: 2022 Flash Rebirth: 2022 Brightest Day: 2022 Return of Bruce Wayne: 2022 Batman Inc: 2022 War of the GLs: Dec 2022 Flashpoint: Jan 2023 Kents move to farm: 2023 Court of Owls: 2023 Death of the Family: Feb 2023 Simon Baz debuts: 2023 Throne of Atlantis: 2023 Superman Unchained: 2023 Damian killed: 2023 Forever Evil: 2023 Damian returns: 2023 Batman endgame: 2023 Darkseid War: June 2023 DCU Rebirth: July 2023 Gotham Knights form: 2023 Super Sons: 2023 Kents return to Metropolis: 2023 I am Bane: Aug 2023 Batman/Flash The Button: 2023 Oz Effect: 2023 Dark Nights Metal: Sep 2023 Gotham Knights disband: 2023 Flash War: 2023 Heroes in Crisis: Oct 2023 Doomsday Clock: Oct 2023 Jon Kent returns from future: Nov 2023 Three Jokers: Nov 2023 City of Bane: Nov 2023 Joker War: Dec 2023 Dark Nights Death Metal: Dec 2023 Endless Winter: Jan 2024 Infinite Frontier: Jan 2024 Warworld Saga: Jan 2024 Fear State: Jan 2024 Death of the Justice League: March 2024 Dark Crisis: March 2024 Flashpoint Beyond: March 2024 Batman failsafe: March 2024 Lazarus Planet: April 2024 Knight Terros: April 2024 Gotham War: April 2024 Beast World: May 2024 Batman dark prisons: May 2024 Absolute Power: May 2024 DC All-In (present day): June 2024

I guess it's more of the Marvel/DC everything happened in 13 years rule. But I'm happy with this. Although I think it should closer to 20-30 years. But this works imo. Do you agree? Do you hate this? What do u think?