38Pres, As the saying goes "Give that man a cigar."

Yes, It is all about the cancels! Here is the explination.
Numbers RJA42-RJA74 are all on watermarked paper and were produced Imperf. and Rouletted. Usage dates were 1919-1964.
Numbers RJA75-RJA104 are all on
UNwatermarked paper and were produced Imperf. and Rouletted. Usage dates were 1963(aprox)-1970.
Now knowing this look at the cancel's. If a stamp was canceled in the 1930's can it be unwatermarked? Obviously, No it can't. Back dating on these is not known to have been done. 1963-1965 it can go either way.