Hi @mikewoodworth, please see the documentation updates we landed in #466 as well as my Forum post from a couple months ago. Swift 6 development snapshot toolchains are required to build swift-testing now, and our intention is to release the first stable version in alignment with Swift 6.
If you've seen conflicting information, please let us know where, so we can try to correct that! It's possible we overlooked some places that need to be updated.