The times at which different Wal-Mart stores sell their deli trays at discounted prices vary from location to location. The best way to find out what time of day a local Wal-Mart normally discounts its deli trays is to ask an employee in the deli section.
As a rule, Wal-Mart stores do not have a standardized time when their deli sections put out older or outdated deli trays for sale at a discount price. There is, however, a rule that a rotisserie chicken cannot sit out for longer than four hours without being discounted.
Once meat from Wal-Mart's regular meat section becomes outdated, the store puts it out for sale at a discount price, usually when there is not a lot of traffic in the store, such during the night or in the early hours of the morning. Discounted deli trays are most likely to be put out for sale at the same time as these discounted meats.