Hello Erwin!
Commander in that period was Generalmajor Grall (13.7.17-22.6.18), * 1.3.1859 ; + 27.10.1943
I couldn´t find him after June 22, 1918, so he probably became off duty since july 1918.
In july 18 the brigade constisted of:
Res.Rgt.221, 222 and 223 and 5./1.Garde-Dragoner-.Regiment.
http://wiki-de.genealogy.net/96._Reserve-Infanterie-Brigade
The brigade belonged to 48th Res.Div.
The division was in reserve in Alsace until April 1, 1918 and left that area on April 14 to stay southwest of Vieux Berquin (30km west of Lille) until end of may. The photo must have been taken in that sector.
Which badge does the officer far right wear?
Here is a british map of april 1918:
http://nickpowley.com/wordpress/?page_id=81
And a german one from end of april: