Many sources give the volume number for this issue as vol. 2, but indicia scans of the immediately preceding and following issues show vol. 1, and the numbering for this series did not excessively strange until later on.
There is a 6-page story with a feature of "Devil Dogs in China" in O.K. Comics (Worth Carnahan, 1940 series) #2. Given that Charles Quinlan was Carnahan's partner in publishing at that time, it's possible that this is a reprint or an until-this-point-unpublished continuation.