[6] The Metrolink 91/Perris Valley Line weekend service began on October 19, 2019 between Perris-South Metrolink Station and Los Angeles Union Station, and consists of 2 round trip trains (one-way to L.A. in the morning and one-way back to Perris in the afternoon and evening).

[7] The Riverside County Transportation Commission (RCTC) purchased the BNSF San Jacinto Branch Line in 1993, soon after Metrolink began operating.

[citation needed] In 2009, both the Federal Transit Administration and RCTC decided to conduct further studies into the project.

The Federal Transit Administration decided to require a Supplemental Environmental Assessment (SEA) to refresh the 2004 information and to obtain new public comment.

RCTC had decided to prepare a full draft environmental impact report (EIR) to clarify concerns and address new station site options.

[8] Originally planned to start in December 2015,[8][13][14] public service on the extension was delayed to February 2016, then March 2016, then scheduled for sometime in the spring.

[25] Construction of an infill station in Placentia is planned, but has been delayed due to a lack of cooperation from BNSF, who owns the right-of-way.