Here is the update that was Posted on Weezer.com 

The Enlightenment tour just got a lot more enlightening! Now confirmed is an expanded line up, with 3 additional bands playing each night on either a Side Stage, or at a nearby alternate venue if no side stage is available. Whats still unclear at this point is when the side stage bands will play- I'm assuming they will be playing earlier, and/or staggered between the main stage acts. For the dates where the additional bands are playing at a separate venue, i'm assuming that concertgoers can use their tickets for both the Main venue and the alternate venue. More details will hit the Tour page as they are discovered.

From July 6th (Salt Lake, UT) till July 23 (Holmdel, NJ), The side stage line up will be Loudermilk, Home Town Hero, and AM Radio. 

From July 24 (Wantaugh, NY) till Aug 10th (Concord, CA), The side stage line up will be Rooney, Home Town Hero, and AM Radio. 

Heres the 'master list' of info as its known:
  Sat- Jul- 06 Salt Lake City E Center; Sparta, Dashboard Confessional, Weezer 

Loudermilk, Home Town Hero, AM Radio: confirmed @ Xcape (downstairs) Sun- Jul- 07 Denver Red Rocks; Sparta, Dashboard Confessional, Weezer 

Loudermilk, Home Town Hero, AM Radio: venue TBD Tue- Jul- 09 St. Paul XCel Arena; Sparta, Dashboard Confessional, Weezer 

Loudermilk, Home Town Hero, AM Radio: venue TBD Thu- Jul- 11 Chicago The World; Sparta, Dashboard Confessional, Weezer

Loudermilk, Home Town Hero, AM Radio: Side Stage Fri- Jul- 12 Detroit DTE Energy Center; Sparta, Dashboard Confessional, Weezer

Loudermilk, Home Town Hero, AM Radio: Side Stage Sun- Jul- 14 Toronto Molson Amphitheater; TBA, Dashboard Confessional, Weezer

Loudermilk, Home Town Hero, AM Radio: venue TBD Mon- Jul- 15 Cleveland Blossom Music Center; Sparta, Dashboard Confessional, The Strokes, Weezer

Loudermilk, Home Town Hero, AM Radio: Side Stage Wed- Jul- 17 Indianapolis Verizon Amphitheater; Sparta, Dashboard Confessional, The Strokes, Weezer

Loudermilk, Home Town Hero, AM Radio: Side Stage Thu- Jul- 18 Columbus Polaris Amphitheater; Sparta, Dashboard Confessional, The Strokes, Weezer

Loudermilk, Home Town Hero, AM Radio: Side Stage Sat- Jul- 20 Hartford ctnow. com Meadows; Sparta, Dashboard Confessional, Weezer 

Loudermilk, Home Town Hero, AM Radio: venue TBD Sun- Jul- 21 Boston Tweeter Center; Sparta, Dashboard Confessional, Weezer

Loudermilk, Home Town Hero, AM Radio: Side Stage Tue- Jul- 23 Holmdel Garden State; Sparta, Dashboard Confessional, Weezer

Loudermilk, Home Town Hero, AM Radio: venue TBD Wed- Jul- 24 Wantaugh Jones Beach; Sparta, Dashboard Confessional, Weezer 

Rooney, Home Town Hero, AM Radio: venue TBD Fri- Jul- 26 Philadelphia Tweeter Center; TBA, Dashboard Confessional, Weezer

Rooney, Home Town Hero, AM Radio: Side Stage Sat- Jul- 27 Washington DC Merriweather Post; Sparta, Dashboard Confessional, Weezer

Rooney, Home Town Hero, AM Radio: Side Stage Mon- Jul- 29 Atlanta HiFi Buys Amphitheater; Sparta, Dashboard Confessional, The Strokes, Weezer 

Rooney, Home Town Hero, AM Radio: Side Stage Tue- Jul- 30 Nashville AmSouth Amphitheater; Sparta, Dashboard Confessional, The Strokes, Weezer

Rooney, Home Town Hero, AM Radio: Side Stage Thu- Aug- 01 Houston Cynthia Woods Amphitheater; Sparta, Dashboard Confessional, Weezer 

Rooney, Home Town Hero, AM Radio: Side Stage Sat- Aug- 03 Dallas Smirnoff Amphitheater; Sparta, Dashboard Confessional, Weezer 

Rooney, Home Town Hero, AM Radio: Side Stage Sun- Aug- 04 San Antonio Verizon Amphitheater; Sparta, Dashboard Confessional, Weezer 

Rooney, Home Town Hero, AM Radio: Side Stage Wed- Aug- 07 Phoenix Cricket Pavilion; Sparta, Dashboard Confessional, Weezer 

Rooney, Home Town Hero, AM Radio: Side Stage Fri- Aug- 09 Irvine Verizon Amphitheater; Sparta, Dashboard Confessional, Weezer 

Rooney, Home Town Hero, AM Radio: Side Stage Sat- Aug- 10 Concord Concord Pavilion; Sparta, Dashboard Confessional, Weezer

Rooney, Home Town Hero, AM Radio: Side Stage

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