For this school project the answer is below:
Yes, the consumers do have claims against Redfern and a right to the merchandise they ordered.
Normally, an advertisement is NOT a contract, it is only an offer to negotiate with consumers. However, in some instances, such as when "bait and switch" schemes are employed or where retailers purposely misrepresent information to consumers, state consumer protection laws can allow consumers to sue retailers for these misleading or fraudulent practices.
In this case, however, Redfern seems to have made an honest mistake. Moreover, his advertisement does not guarantee a supply of the sale items will be available to all nor does it say rainchecks will be provided if products run out. In short, it does not seem Redferm mislead or misrepresented anything nor that Redfern tried to bait and switch consumers. Those who arrived to late to participate in the sale would normally not have any claims they could make against Redferm.
However, as explained here, Redfern seems to have taken orders (the information says "there were several unfilled orders," suggesting that Redfern took orders instead of telling the buyers that no more were available) from consumers for items at the sale price. By taking those orders, at a specific price, Redfern entered into contracts with the consumers to sell them those items at the sale price and he is required to fulfill those orders or he will be breaching his contracts with the consumers.