How can there be three unreleased songs when we were told the box set had them all?!????!?!?!

New Nirvana Compilation On The Way
Just in time for the holidays, DGC has set a Nov. 1 release date for a new Nirvana compilation. “Sliver: The Best of the Box” rounds up highlights from the last year’s boxed set “With the Lights Out” and will also feature three previously unreleased tracks, details of which have yet to be revealed.
“With the Lights Out” was a quick hit, debuting at No. 19 on The Billboard 200. It was the biggest sales week for a boxed set since Garth Brooks’ “The Limited Series” in 1998 and has shifted 429,000 copies in the United States, according to Nielsen SoundScan.
The box was originally intended for release in Christmas 2001, to coincide with the 10-year anniversary of Nirvana’s breakthrough album, “Nevermind.” But surviving members Krist Novoselic and Dave Grohl were thwarted by lawsuits from Kurt Cobain’s widow Courtney Love, who objected to their planned use of the previously “You Know You’re Right” in the set.
The dispute was eventually settled in September 2002, with the parties agreeing to earmark “You Know You’re Right” for a self-titled Nirvana compilation released the following month.