Fall 87 was the 1st. 88 had 2 issues summer & fall winter was called 89. also in 89 spring summer fall 4 issues. 90 to 93 had Feb April June Aug Oct Dec. 93 switched to Jan March May July Sept Nov. 6 issues 90 to 95. 95 has 7 issues. 96 to? has 8 issues.
From CTT May 97 page 154