I tried getting the date amended through the Make Corrections page months ago...! (Sure, I only had the label design to go off, but my suggestion of 1939, at the most, was a lot more accurate than 1950.)
Not released in 1950 as originally entered but in Dec 1938. Must have been a long seller in Australia though. As said on the back cover of an EP with all four parts there, "in 1956 it sold more than twice as many copies as it had in 1938".