The Niantic Support tweet announcing the new date also noted to "stay tuned for details". Niantic Support on Twitter is at NianticHelp.

#PokemonGO #Mewtwo #ShinyMewtwo #Psystrike #RaidHour #LegendaryRaidHour

There is normally no extra Raid Passes for Raid Hours but this serves as compensation for the inconvenience.
Upcoming Events: leekduck.com/events/

#Mewtwo #ShinyMewtwo #PokemonGO #Psystrike #RaifHour #LegendaryRaidHour

Armored Mewtwo strikes back in 5-star Raids later today with the special Charge Attack Psystrike.
Save a copy: leekduck.com/events/

#PokemonGO #Mewtwo #ArmoredMewtwo #PokemonDay2020 #ClonePokemon #Psystrike

If you need confirmation.

Track Events: leekduck.com/events/

#ArmoredMewtwo #PokemonGO #LegendaryRaidHour #Psystrike

Pokémon Day 2020 Event - Overview and Summary⁣
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• The event spawns are Pokémon featured in 'Pokémon: Mewtwo Strikes Back—Evolution'⁣
• 7 km Eggs are only hatching Party Hat Starters. (No Fossils)⁣
• Clone Pokémon CANNOT be shiny⁣
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Full Event Details: leekduck.com/event/⁣
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#PokemonGO #Mewtwo #ArmoredMewtwo #PokemonDay2020 #Psystrike #ClonePokemon #CloneVenusaur #CloneCharizard #CloneBlastoise #FrenzyPlant #BlastBurn #HydroCannon #PartyHatBulbasaur #PartyHatCharmander #PartyHatSquirtle

The Throwback Challenge: Kanto event runs from May 1, at 1 pm local time to May 8, at 1 pm local time. ⁣
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Here's what to look forward to in our look back at the Kanto region. ⁣
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See what's spawning: leek.gg/kanto⁣
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#PokemonGO #Bulbasaur #Charmander #Squirtle #Kanto #ThrowbackChallenge #Mewtwo #Psystrike #Charizard