Perhaps a clue from feldgrau.net
"As a result of the aerial combat which took place on November 6, 1939 against 9 French Hawk H-75 (GC II. / 5) escorting a reconnaissance plane Potez-63, two squadron leaders were killed in action; Oberleutnant Waldemar v. Roon of the 1./ JGR 102 (replaced by Hauptmann Armin Ettling) and Oberleutnant Joachim Kellner-Steinmetz of the 3./ JGR 102 (replaced by Oberleutnant Eberhard Sauer). Four other aircraft made forced landings with serious damages and one injured pilot.
"Hauptmann Armin Ettling took command of the 1./JGr 102 from December 13, 1939 onwards. He was a veteran of the Legion Condor as Leutnant he had won the Spanish Cross in Gold in the J/88 and was awarded the Iron Cross 2º Class in 1939; later he assumed command of the 7./JG 2."
Sources:
http://forum.panzer-archiv.de/viewtopic.php?t=8741
Der Adler Nº 21 1939.