Every plant maintains their own trucks. Goods to customers surrounding any plant will be delivered using these trucks.
Let's say Plant A is in North California......Plant B is South California. We use trucks in Plant A to delivery goods to Customers in North California(close to Plant A).
Trucks in Plant B can't deliver products to Plant A customers. We put trucks to run once or twice a day, between Plant A and Plant B (to full orders in Plant A when stock is not available)
This is why we thought of using this process.