Airport authority officials have released a tentative opening date next year for the Washington Metropolitan Area Transit Authority’s Silver Line extension.

Metropolitan Washington Airports Authority officials said the Metro’s six new stations, which extend service to Ashburn through Washington Dulles International Airport, are set to open on or near July 16, 2020, provided there are no further delays in construction, WTOP reported Monday. Construction on the project has previously been delayed several times, costing at least $95 million in 2017.

The project was most recently delayed in June for an additional two months because Hensel Phelps, the company responsible for building the project’s rail yard, and Capital Rail Constructors, the contractor building the tracks and stations, both fell behind schedule. Metro’s latest contracts with the two companies call for construction on the project to be completed this week, WTOP reported.

“After all of our examinations and statistical analysis, we are confident at this point in time — without any unforeseen situations or problems — that we will be opening in the middle of July of next year,” Charles Stark, the airports authority senior vice president for the Dulles Corridor Metrorail Project, told WTOP.

Other project stakeholders have cast doubt on the airport authority’s projection for the extension’s completion. WMATA officials have not agreed to the airport authority’s projected date, citing the need to conduct safety testing before the line opens, and Hensel Phelps has predicted the rail yard will not be ready by July.

“Metro will establish a revenue start date once the project, including the rail yard, has been completed to our standards and requirements and accepted by Metro for final testing and safety certification,” WMATA spokesman Ian Jannetta told WTOP in an email.