Tactical Symbol question?

A question for you to answer?

The photo is from World at War issue "What if Hitler went East?"

and is a from the German army disposition OOB from 1940

Now the Question is what is the line around the the Army Group "Kliest" represent?:

 And again over the Divisional unit "Verfuhgungs" which is the fore runner of Das Reich ala 1942 when numbering also was started (later)

Any answer greatly received, it is annoying me, But not losing sleep YET??

cheers Karcuss