Some labels for a time put a date at the beginning of their master numbers. This would show the releases for that year. The next year would start at the bottom of the numbering sequence. Labels that did this were; VJ, Tollie, MGM, and Cub. RCA also did this from the late 40 to the early 60s. They used a letter and a number to denote the date. D8 would be 1948; E4 was 1954. In 1956 they changed again with F being 1956, G being 1957 and H being 1958. And they skipped I for 1959.