According to this research ... anation-fun-facts-drawing, it first appeared in 1980 UT 1st ed. (without the 8 dots) and 1983 HoMe1 1st ed.(identical to current form). Are those two the earliest?

Also, in all Tolkien's written monograms I know(, he never used the standard one with 8 dots (and all the examples I know are before 1937). Did CRRT design the standard monogram based on some unpublished later manuscript? Has he explained why adding the 8 dots in HoMe1?