Hey, the CBR main page updated with this new info about SOS:
If you've been reading this forum for the past few months, you know that I'm quite upset with Beast's turn to pitch-black villainy. He's become exactly like Dark Beast. But now it seems that Sinister has been manipulating Beast to be like this by tampering with time. Others, like Kurt who's turning into a real demon, are also affected.The X-Men will experience another reality-altering event in January of 2023 when the Sins of Sinister launches. Mr. Sinister has been plotting and scheming since the launch of the Krakoan Era, and his plans will come to fruition.
The Sins of SInister will alter reality much like the popular Age of Apocalypse event from the ‘90s. The event will feature a number of tie-in issues that will explore the Marvel heroes in their new Sinister-influenced forms. The Sins of Sinister will also feature characters from the X-Men’s dark future that first appeared in Powers of X and promises to shake up Marvel’s mutants.