Thanks Regulus and Rick for your assistance..
..and Rick, I am convinced now(after checking some sources) that his family name should be spelled Evers.
On the other hand, I have him in Küsta IV from late Apr 1918 until sometimes Jun-Jul 1918 when he went over to Küsta III, probably taken over the command when Leffler left.
Sadly I cant refind my notes when Leffler left for his Stab duties...

Gunnar