FYI the latest Vader Issue #11 has a ton of new context about Palpatine on Exegol

**Big Spoilers**
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TIMELINE POST-ESB (3 ABY), PRE-RoTJ (4 ABY).
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Palpatine was already growing Pickled Snokes in vats and already constructing the Planet- Armada, pre-dating the FO.

Also there's a huge HUGE thing in his possession that could change a lot of stuff if it was used in the creation of his strandcast Son. If the clues are pointing the right way, more Rey Skywalker Rights.
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***Spoilers***
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Hux is about 3-4 years old when this is happening, at Arkanis Academy under the control of his father.

Poe is 1-2 years old with his parents fighting the war.

Kylo is still a twinkle in his father's eye.

Means the Final Order didn't use SKB tech in their armada and it's just Palps continued kink of planet destruction a la Project Cinder.

Snoke's creation had nothing to do with Kylo and is most likely just a surviving specimen of Palpatine's experiments being put to use.

Vader is very unimpressed