Speaking to Warcraft Wiki representative Kaydeethree, Blizzard representatives have spoken about the upcoming World of Warcraft expansions making up the Worldsoul Saga. In order to speed up the process, they revealed that "Teams have been parallelized, they're already working on Midnight."
Midnight is the second chapter in the trifecta of Worldsoul Saga expansions, which will be coming alongside The War Within, and The Last Titan.
Associate Design Director Maria Hamilton and Lead World Artist Kristy Moret spoke at a BlizzCon 2023 panel, making it clear that "Zones and story in Midnight are already underway." They're essentially further confirming that the devs aren't just one-at-a-timing.
"We're very good now at working at multiple things simultaneously, and have built out that pipeline to be able to work on expansions in parallel."
As one person who posted the news on Twitter (or X), Ian Bates, notes "I'd hope the simultaneous development helps prevent the kind of inconsistencies we've seen from a loser way of planning multi expansion storylines, but that depends on how much the separate teams working on different expansions communicate with each other."
The team say they also "want to finish the Worldsoul saga before 2030." With another spokesperson noting, "We want to ensure that players aren't completing this saga in 2030. Teams have been restructured to be able to create this whole saga."
So there's a lot of internal movement to get the expansions over to us sooner rather than later, though whether this parallelising will prove a deficit or a boon is another matter entirely.
As one commenter points out on X, "I genuinely don’t think I like the idea of faster and faster expansions, I feel like unless they do something specifically well they’ll feel too rushed tier and schedule-wise."