So apparently the first film of this new trilogy has begun pre-production:

https://www.fanthatracks.com/news/film-music-tv/star-wars-tv-production-begins-in-the-u-k/

“Registered on the exact same day was E&E INDUSTRIES (UK) LIMITED which we understand will be the first film from the planned Rian Johnson trilogy. It should be noted that for convenience Disney register businesses in blocks, and the creation of these businesses does not mean they started production at those dates, merely that they intend to enter production soon. This can of course mean very early design development, and does not necessarily mean they will see final production, as seen recently with PLT Productions (the Kenobi movie.)”