(CNN) - Costco’s controversial shopping policy will officially take effect on Tuesday.

Back in June, the grocery warehouse chain started allowing Executive Members into the store from 9 a.m. to 10 a.m. during the week.

Customers with other memberships had to wait until after 10 a.m. to begin shopping at that time.

The company said the policy was not strictly enforced then.

But now, Costco says its grace period is ending and the policy will take hold on Monday, when stores will be closed for Labor Day, and shoppers will notice the difference on Tuesday, Sept. 2.

Some customers are not happy with the change. They say Costco is favoring its higher paying members and alienating the rest.