WASHINGTON (AP) — A major change to Metrorail service is getting under way.

Metro is rolling out its “Rush Plus” service Monday morning. The change will affect about 110,000 riders on the green, yellow, blue and orange lines. The service will be in effect weekdays between 6:30 a.m. and 9 a.m. and between 3:30 p.m. and 6 p.m.

Metro says 21 stations will see an increase in the number of trains with the service. On the orange line, customers will find six additional trains per hour between the Vienna and Largo Town Center stations. Metro says that will result in 18 percent more capacity on the line.

Metro says there could be some confusion Monday. Spokesman Dan Stessel says riders need to pay close attention to the destinations of the trains they’re boarding.

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