The first version of the direct-drive mechanism was spin-drain, from introduction in 1981 (Kenmore) through late 1984.
The first Whirlpool model was LB5500XKW0 (K = 1982). I remember selling it and pulling them from the warehouse stock when working at the WP dealer. The service manual L-46 "Design 2000 Direct Drive Washer" is dated 1981.
Granny had a spin-drain machine. LA7400XMW2 (M = 1984), serial of C435 (35th week Aug 27-31 of 1984).
Whirlpool service manual L-52 "Design 2000 Washer with Neutral Drain" is dated 1985. It references model LA7460XM (M = 1984) in the timer sequence charts that detail the motor pauses. It also references 1) production of 27" models, 2) an increased 10-yr parts warranty on the plastic outer tub beginning with serial C446 (46th week Nov 12 of 1984), and 3) a new shipping-strap system. That reference does not explicitly make clear if Nov 12 1984 was the beginning of neutral drain production but one can perhaps conclude it.
Another change that occurred at some point is the transmission mount orientation was rotated. The motor (and pump) was originally at the right rear corner, not at the front. Photos in L-46 show it at the right rear corner.