How does Amazon FBA Upgrade work and what is required?
When calculating a seller's current inventory level, Amazon generally takes into account several factors, including the seller's inventory in the Amazon logistics centre, shipped inventory that is about to be warehoused, and any inventory removal requests that have been processed.

When a seller's inventory is restricted, Amazon will send a notification to the seller's account and email address, and the seller will no longer be able to ship to FBA warehouses until the seller's inventory level falls below the storage restriction limit.

1, sellers should use FBA for at least 4 weeks, and above 6 weeks is the best.

2, the seller's sold out rate in the past 6 weeks - sold out rate is equal to the weekly sales volume divided by the weekly inventory, Amazon requires sellers to sell out rate should be greater than or equal to 8%, the inventory can be obtained through the seller's platform inventory report.

3, WOC-week of coverage is equal to the seller's current inventory level divided by the average weekly sales volume over the past 4 weeks, the indicator mainly looks at the seller's inventory can still be maintained for a few weeks can be consumed.

The shop's inventory plays a very large role in Amazon shop operations, so whether or not it can be upgraded is also something sellers are very concerned about. Amazon looks at the seller's warehouse limits every month, and if the seller has been able to sell 8% or more of their inventory every week for the past 9 weeks, they are eligible for an upgrade, and the seller can contact Amazon to request an upgrade.

Sellers requesting an upgrade need to be aware of the current inventory turnover rate and inventory type and other factors, Amazon is based on the specific circumstances and then make a decision on whether to give the seller an upgrade.

If the seller has been out of stock, they can also take to sell their listings, raise prices, emergency replenishment and other methods to remedy to reduce the impact on the shop.

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