Rule 4.b. states, “Once competitors enter the cordoned-off competition area to trim, practice, or compete they must ....not receive outside assistance, materials, or communication.” Does this apply to open practice the day of competition?

Yes, this rule applies to Open Practice the day of competition. The rule is specific including trimming, practicing and competing. Coaches & students are not allowed to interact in the cordoned off practice area the day of the competition.