The series is continuing, but each story in the arc pretty much stands alone. Although some things are left unresolved from story to story, there are no cliffhangers.
I love this series, even though it has way too much Duo-angst in it. I think the early stories are the strongest, especially Assumptions and Evasions. The stories start during the war, but mostly take place afterwards, when Duo takes a dangerous salvage job that goes badly wrong.