Frame #C -- Pre-Launch Mechanics

Hands & Lead-Shoulder Rotation (Shrug)
The inward turn of the knee and hip are complete, but the inward turn (shrugging) of the lead-shoulder continues as the lead-arm reaches across the batter's chest (taking the slack out). The hands are moving toward the back-shoulder causing the bat-head to continue accelerating back toward the launch position.

Weight Shift and the Soft Stride
Barring the Arm & Shrugging the Lead-Shoulder
Hands that Creep Forward or Away from Shoulder