Slugs taking metro from the Pentagon to Rosslyn will be affected during this metro disruption from 08/11 - 08/26.

Metro rails will be single tracking between McPherson Square and Smithsonian from 8/11 through 8/26. This will significantly reduce rail throughput and all blue line trains will only go as far as Arlington Cemetery. It is suggested that people use the Yellow Line into DC and then backtrack on the Silver/Orange line. ART 43 is also an option for those from Crystal City to Rosslyn/Court House as are Omniride routes.

From Pentagon to Rosslyn/Ballston, passengers can transfer from another Omniride route to the D200 trips that continue into the Rosslyn corridor. If they are in Crystal City, they can use the ART 43, especially if they slug or VRE in to that area.

From the west, the Orange and Silver lines will still be running.

Here’s some links to various services that may help:
https://www.arlingtontransit.com/pages/routes/art-43/
http://prtctransit.org/commuter-bus/schedules/dalecity-pentagon-am.html

https://sluglines.com/blue-orange-silver-line-disruption-aug-11th-aug-26th-2018_page_1