I take an item, and send it to Amazon warehouses, so that it'll be available as FBA.
I then list it on AZ....as FBA.
I also list it on EB.
My plan is to have AZ ship it, if someone buys it from EB.
When someone buys it on eBay, will SB auto-reduce the item on AZ, to zero? Even tho it's still in FBA, until I trigger the fulfillment?