I don't think they will have an event in 2022 and 2023. Since the Expo is where they announce major projects, I don't see how they can have that many projects to announce to hold events in back to back years especially in the financial situation they're in now.
Most likely, it'll be 2022, then 2024. If it's in 2024, they could preview
Disneyland's 70th anniversary.
I do see a scenario where they go 2022, then 2025...again because of the current financial situation and with projects getting postponed.