Using "of" vs. "on"

I have been getting confused whenever I use the following sentence.

1. "Change the materials on the customer order" vs. "Change the materials of the customer order"
   Since the materials is assigned to the customer order, wouldn’t "of" be more appropriate, but "on" sounds more correct.

2. "Schedule production on these materials" vs. "Schedule production of these materials"
   These two confuse me as the following sentence sound more appropriate using "of."
   "Production of these materials will take place in November." — In this case, we cannot use "on."

Thanks in advance!