The article that started this particular thread does not reflect the full timeline of the 1st Atlanta United game at the Benz.
April 16, 2014
Arthur Blank (AMB) was awarded the Atlanta United franchise on April 16, 2014, and a big part of AMB getting the franchise was the new stadium being ready for MLS play. In fact, AMB had originally applied for a franchise in 2008, but had to withdraw the application due to the lack of a suitable stadium (Wiki : As the largest metropolitan area without an MLS franchise, Atlanta Falcons owner Arthur Blank's AMB Group submitted a bid in 2008 for an expansion franchise, but withdrew the bid in early 2009 due to its inability to get a stadium built.)
January 2016 the new opening date for Atlanta United at the Mercedes-Benz Stadium is set as June 1, 2017.
From the AJC article (my bold-facing)
Posted: 6:23 p.m. Thursday, January 21, 2016
Construction of the downtown stadium that will become home to the Atlanta Falcons and a new professional soccer team won’t be completed in time for a long-planned March 2017 opening.
The new target date for completion of Mercedes-Benz Stadium is June 1, 2017, Arthur Blank, owner of the Falcons and Major League Soccer team Atlanta United, told The Atlanta Journal-Constitution in an interview Thursday.
October 2016 The start of this thread. Opening date for the stadium is pushed back to late June, early July.
January 2017 New opening date set as July 30, 2017. Is this the final change? Who knows?
I'm using the April 16, 2014 date as the first time it is announced there will be a MLS game at played in the new stadium at the start of the 2017 MLS season, and so the opening date has since slid about 4.5 months (early/mid March - late July). From mid-April 2014 - mid-2017 is 35 months making the 4.5 month delay about a 14.5% delay (if my math is correct).
Is a 14.5% delay "normal" for this size of a project?