first month dsm's were made?

[Eclipse90GSX]

hey guys, whens the first month dsm's were made? i know it was in 1989, but what month was it? it had to be n the last 6 months right? otherwise theyd be dubbed 89 as the first year?

my sticker says nov 1989...

 

[gigahz95]

no, 89s would have been made in 88. I think mine was made in february 89.