http://forums.harmonixmusic.com/discussion/282896/introducing-the-rock-band-season-2-spotlight-pass
Rock Band 4 has a new Rivals mode where each week crews (basically 10 person bands) compete for high scores. There's 3 songs per week. This guarantees you 8 new songs, which would usually be 16$ USD total @ 2$ USD each for 13.50$ (so in line with existing pack discounts), at a rate of one new song per week for 2 months.
It's also been confirmed they are NOT counting Rewinds (songs from previous Rock Bands) in this. 100% new songs.
Brand new to Rock Band this month – a season pass to select, new Rock Band DLC. Each week for the duration of the season (eight weeks), players who purchase the Season 2 Spotlight Pass will be granted a permanent entitlement to whichever new release is featured as a Spotlight Song in that week's Rivals Mode challenge (a total of eight songs). The Season 2 Spotlight Pass will cost $13.49 and be available for purchase beginning August 24 on both Xbox One and PlayStation®4 for the duration of Rivals Season 2, which ends on October 17, 2017.
Rock Band 4 has a new Rivals mode where each week crews (basically 10 person bands) compete for high scores. There's 3 songs per week. This guarantees you 8 new songs, which would usually be 16$ USD total @ 2$ USD each for 13.50$ (so in line with existing pack discounts), at a rate of one new song per week for 2 months.
It's also been confirmed they are NOT counting Rewinds (songs from previous Rock Bands) in this. 100% new songs.