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First you can block or discontinue an item. This will prevent the user from purchasing this item entirely, they will not be able to send an order out with this item on it.
Second you can provide a replacementreplacements. Replacements will allow the “to be replaced item” to still exist and be ordered, but will provide the alternatives you select when validating. (Please note, the replacement is shown to the customer at the time of validation, but it is not forced selection. The customer has the option to opt for a different substitute if they so choose.)
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