The Conflict on Kashyyyk was one of the many battles that took place there, starting in 19 BBY Month 28, and ending in 19 BBY month 31.
During this battle, the Phase II armor was just being invented.
Many skirmishes were fought during this conflict.
The Skirmish for the MMAS/AATSEdit
General Grievous landed on Kashyyyk, and gave the orders to kill the Jedi. But this time, he'd be testing a prototype for an extremely useful speeder, the Missile Assault Speeder. It was a variant of the AST, with advanced armor and a missile launcher. Alpha-81 was sent to investigate. He crossed a bridge, just as the MAS got to it. Quickly drawing SARC/661138's Z-6/PLX-1.5(which was temporarily in his possession), he defeated it. If the Speeder would've crossed the bridge, it would have probably killed Wan Dee.