This article explains a lot.
"As Deadline
has reported, the Season 3 delay stemmed in part from the fact that, while Saldaña already had an acting deal in place spanning three seasons, Kidman had to make a new one for Season 3, which took awhile. It closed earlier this year when Season 3 was quietly greenlighted but not announced as producers had to work around its two stars’ busy film schedules. The long gap between Seasons 2 and 3 saw Saldaña join Kidman in the Oscar winner ranks for her performance in
Emilia Pérez."
"Word of Lioness getting a third season got out in August when a new production campus in Fort Worth Texas’ AllianceTexas development was officially unveiled as a partnership between SGS Studios, Sheridan’s company with 101 Studios CEO David Glasser; Paramount Television and Hillwood, a Perot Company.
Glasser, whose 101 Studios co-produces all Sheridan series alongside Paramount TV Studios, revealed at the time that four shows were slated to film on the lot this year, starting with
Landman Season 2, followed by
The Madison Season 2 and
Lioness Season 3, slated for an October start."