The timeline yes, but not what you do with that time. Concepts that where planned for 9.3 could easily be brought into 9.2 or vice versa and most of the work that would have been needed to realize a potential 9.3 just shifts towards the team that’s working on 9.2 or already heavily involved on the creation of 10.0. Pretty easy to do because 9.3 at this point is barely more than a concept. 9.3 PTR, if it exists, is 12 months away. And by concept I mean they have already done this before the launch of Shadowlands. So that’s not even work that’s been wasted, when it never was more than an idea on paper.
And we know what usual .1 patches contain. We know what 9.1 contains. We know who is part of 9.1 already (most of the Jailer’s allies, Kel’thuzad and the lore heavyweight Sylvanas) - we’re basically just missing Arthas and Anduin at this point to finish the Jailer storyline and both of them are part of the final Jailer story (e.g. the final raid), one way or another.
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9.1: We’re invading the Maw, we’re heavily abusing the Oribos port stone, we most likely lose, the Jailer uses the port stone...
9.2: The Jailer teleports to the other Shadowlands’ zones and eventually Oribos, in Oribos he kills the Arbiter (or whatever) and teleports to Azeroth, we fight him in Azeroth on top of Icecrown, Anduin becomes the new Arbiter (or Arthas? Who knows) - end of the Jailer storyline.
Plots like Garrosh in the Shadowlands? Interesting, but who cares.