As products age, the manufacturer of the product may design an upgraded version of that product for sale. Releasing this new version is known as product supersession, where the new version supersedes the old version of the product.

Once a product has been superseded by a newer product, it can be run out or both versions can be sold until stock runs out. 

Running out stock is when all of the product that has been superseded by another one is sold first before starting to sell the superseding, newer product. This allows the product to be cleared before the superseding product becomes available for customers.

There can be a chain of superseded products as newer products are introduced, where multiple versions of the same product are superseded by one another. For example, product A is superseded by product B, superseded by product C, which is in turn superseded by product D. 

Any product that has been superseded by another product, cannot then supersede a product. For example, product A cannot be set to be superseded by product C, if product C has been superseded by another product previously. Additionally, a product cannot supersede itself.

Within the Settings module, different types of transactions can be set to run out the obsolete product. These four transaction types are quotes, invoices, transfers and POS transactions, and can be set that any of them do use run out and others don’t. These settings are located in the Products Settings portion of the Settings module - https://infusion.helpjuice.com/en_AU/products-settings/settings-%7C-product-settings