Chris,
According to website
www.ww2.dk, 2./606 had Do.18 at Hörnum during the date in question; 2./906 didn't acquire Do.18 until October 1939. Seems to be at odds with your view? Rather like Stig and Shores, I thought that
www.ww2.dk was a highly dependable site. All I want is the truth and am willing to be persuaded...
I don't understand your last sentence. Do you mean that the 612 Sqdn file for Sept. '39 should be examined at the NA?
Bill