Back Ordered Fulfillment is simply this order is on its way to us but can not get to us and then shipped to you within our normal shipping days. If this happens we will let you know by the next business day which items are on their way to us and the approximate expected shipping date to you. If our providers are also back ordered we will let you know this as well. It is very unusual for our providers to back ordered as well however, when this happens we are at the mercy of them. If we can find an alternate provider at the same rate then we will do so.