Question about how ShipHero pushes inventory count to Amazon

Note: this question was posed to customer service with ticket 73314 and I was told to post here.

We are trying to debug a situation where we update the handling time (fulfillment latency in Amazon speak) on items in Amazon and then, when they sell, find that the latency has reverted to 1 day.

For example, order xxx-xxxxxxx-7408215 contains item UE21457. We had previously set the fulfillment latency on this to 4 days, but the order came through with a latency set to 1 working day.

Our current hypothesis is that the fulfillment latency is being reset to a default when inventory updates are made from a third party (e.g. ShipHero). This, of course, is no fault of the third party integration.
We want to collect information for debugging purposes before contacting Amazon. Can you let us know the following:

  • How do you send inventory updates to Amazon? Is it through a _POST_INVENTORY_AVAILABILITY_DATA_ feed? (I’ll assume that the feed would not contain the FulfillmentLatency field, if so)
  • Do you send full inventory counts or just entries for items that have changed since the last quantity change?
  • How often are these sent?

If it turns out that the FulfillmentLatency is overwritten on each inventory feed, we will obviously have to re-think our approach or take over submitting this to Amazon.


@tomasw Just wanted to tag you to see if you had any insight into this…

Hi @david!
I apologize for the back an forth about this. You are right, it is not Public API related, but let me ask around to see if I can get more insight about this from our engineers working on the Amazon integration.
I will let you know as soon as I get more information about it.
Thanks in advance!

Hi @david!
I apologize for the delayed response.

We don’t currently send the FulfillmentLatency field to Amazon. We do send the feed over to POST_INVENTORY_AVAILABILITY_DATA but it doesn’t contain that field.

We send inventory updates every time the inventory changes for a product. We send the entry for the product that changed

Every time the inventory available number changes, we enqueue it to be sent to the store. We have a task to push the new inventory numbers every 20 minutes.

Let me know if that doesn’t help or I could ask for more information about it.
Thanks again for the patience!

@tomasw, thanks for the answers! This is pretty much what we assumed (and makes sense), but we wanted to rule out anything different before digging in further. Thanks, again!

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Hi @tomasw ,

I noticed in product details on the dashboard (, there is now an Amazon section where fulfillment latency can be set on a product-by-product basis. Two questions:

  1. Does this mean that you will send it to Amazon if it is set?
  2. Any chance that this will be added as a graphql mutatable attribute?


Hi @david!

That is correct

This would need to be set per account per product, so not quite sure if it’s an easy thing to build at the moment, but I can always make a Feature Request to add this. Let me know if that would work for you.
Thanks in advance!

Hi @tomasw

It would be great to add this as part of a (warehouse) product mutation.

The Amazon feed that sets available inventory is the same feed that sets the FulfillmentLatency. The unfortunate side of it is that you can’t set only FulfillmentLatency; you have to always specify quantity available.

For anyone like us, where we have fulfillment latencies that change based on supply chain, we have to run our own inventory update to Amazon. This poses two problems:

  1. If our inventory count isn’t perfectly synced with ShipHero, we run the risk of sending an incorrect count
  2. Amazon has a nasty habit of resetting fulfillment latency if it’s not set. So, when ShipHero sends its update to Amazon, it sometimes, but not always, overwrites our latency.

This would be a huge help, if it can be done.

Makes sense, thanks @david for the explanation.
I sent the request to our Engineering team to discuss internally if we could add this.
We will let you know as soon as we get a resolution on this.
Thanks again for the patience while we figured this one out!