According to an article on HMV & Books (in Japanese), ECM will release J.S. Bach: The Well-Tempered Clavier, Book I in May 2019. This is a live recording of BWV 846-869, recorded on March 7, 1987 at the Troy Savings Bank Music Hall in New York, not to be confused with Das wohltemperierte Klavier, Buch I, a studio recording released in 1988.

HMV lists the album with a release date of May 20, 2019 [This is apparently incorrect, see below.]. A UHQCD (Ultimate High Quality Compact Disc) version of the album will be released in Japan on June 19, 2019. It will consist of 2 CDs, each with 24 preludes and fugues (BWV 846-857 on CD 1 and BWV 858-869 on CD2).

Thanks to "tgwhrk" for the information.

Update (May 8, 2019). J.S. Bach: The Well-Tempered Clavier, Book I is now listed on many online stores. Challenge Records, for example, offers more information and sound excerpts. The correct release date appears to be June 14, 2019, not May 20, 2019.

These are performances in which tempos, phrasing, articulation and the execution of ornaments are convincing,” wrote Gramophone of Jarrett’s first recorded account of The Well-Tempered Clavier. “Both instrument and performer serve as unobtrusive media through which the music emerges without enhancement.” In this live recording from Troy, New York, made in March 1987, just one month after his studio recording of the work, Keith Jarrett addresses the challenges of Bach’s great set of preludes and fugues once more. Part of the goal is transparency, to bring the listener closer to the composer. As Jarrett explained at the time: “The very direction of the lines, the moving lines of notes, are inherently expressive…When I play Bach, I hear almost the process of thought. Any colouration has nothing to do with this process.

Thanks to Boris for the link.