Erprobungskommando Do 335 was established under the
Kommando der E-Stellen on 4 September 1944 to evaluate the Dornier Do 335 as a nightfighter, armed recce and bomber:
http://forum.12oclockhigh.net/album....pictureid=1701
http://forum.12oclockhigh.net/album....pictureid=1702
It was disbanded on 12 February 1945. (RL 2-III/67 p. 0017)
As far as I know, it was never used in combat. This photo is a hoax:
http://forum.12oclockhigh.net/album....pictureid=1703
http://forum.12oclockhigh.net/album....pictureid=1704