Running Seller Fulfilled Prime well isn’t just about hitting your metrics once — it’s about staying ahead of the conditions that put them at risk in the first place. Weekends drag down page views. A single stockout can trigger a cancellation. A slow carrier on the wrong day can chip away at your on-time delivery rate before you’ve even noticed. Watching for all of that manually, every day, isn’t realistic at scale.

The ShipSage OMS is built to handle these conditions automatically. Instead of reacting after a metric slips, you pre-configure the rules once — for Buy Shipping, OTDR protection, ASIN availability, and inventory safety — and the system enforces them continuously. This post walks through each of those configuration tools.

Part 1: Amazon Buy Shipping & OTDR Protection

The first configuration area controls when the OMS automatically uses Amazon Buy Shipping on your behalf. Rather than deciding order by order, you set the conditions in advance:

  • OTDR-based triggers — set a day of the week, or a specific On-Time Delivery Rate threshold that automatically activates Buy Shipping if your OTDR drops below it
  • A maximum acceptable cost difference between Buy Shipping and your regular shipping rate, so automation never quietly overspends
  • The exact percentage of shipments to route through Buy Shipping, and which carrier to use for them

This turns OTDR protection from a manual, after-the-fact fix into a standing rule. If you’re new to what OTDR is and why Amazon enforces it, our earlier post on the OTDR policy update covers the requirement itself in more depth; this post focuses specifically on how ShipSage automates protecting it. Similarly, if you want the fundamentals of Amazon Buy Shipping — what it is and why weekend coverage depends on it — that’s covered in our Buy Shipping for SFP Orders post. What’s new here is the configuration layer: pre-set rules instead of daily manual decisions.
For the full set of required thresholds Amazon enforces alongside OTDR — including tracking rate and cancellation rate caps — see our SFP Tracking Rate post.

Part 2: Auto Disable/Enable SFP ASINs by Size Tier

Why Weekends and Holidays Are the Problem

One-day and two-day page view requirements are hardest to hit on weekends and holidays, and not because of anything the seller does wrong. Carriers frequently don’t work Saturdays, and even when they do pick up, they often skip the origin scan — which means the page view clock doesn’t start when it should. That naturally drags down page view ratios during exactly the window sellers can’t control.

Automatic ASIN Disabling

The ShipSage OMS addresses this directly: you set what percentage of SFP ASINs, broken out by size tier, should be automatically disabled or re-enabled over weekends and holidays. The system also detects which specific ASINs are dragging down your page view ratio and removes just those from the SFP shipping template — rather than pulling every ASIN indiscriminately.
This works alongside the shipping template and ASIN automation covered in our other OMS walkthrough, since both control which ASINs are active in your SFP templates at any given time.

Part 3: ASIN Safety Inventory Automation

The third configuration tool addresses a different failure mode: running an SFP order against inventory you don’t actually have. You pre-configure a safety inventory quantity for your SFP ASINs. Whenever stock on a given ASIN drops below that threshold, the OMS automatically removes it from your SFP shipping templates — before an order can come in against it.

This closes a specific, avoidable failure: cancellations caused purely by running out of stock on an ASIN that was still marked available for Prime orders.

Why This Matters for Protecting Your SFP Badge

Each of these three tools targets a different way SFP performance erodes — shipping cost and tracking discipline, weekend page view drops, and inventory-driven cancellations. Configured once, they remove the daily manual monitoring that used to be the only way to catch these problems before they affected your metrics. That’s the shift this OMS update represents: from checking dashboards reactively to setting rules that hold automatically.

Frequently Asked Questions

What triggers automatic Buy Shipping in the ShipSage OMS?

You can set it by day of the week or by an OTDR threshold — if your On-Time Delivery Rate drops below the percentage you define, the system automatically activates Buy Shipping according to your configured rules.

Can I control how much more Buy Shipping costs compared to my regular rate?

Yes. You set a maximum acceptable cost difference between Buy Shipping and your standard shipping rate, so the automation stays within a cost boundary you define.

How does ASIN auto-disable work over weekends and holidays?

You set a target percentage of SFP ASINs, by size tier, to automatically disable or re-enable during weekends and holidays. The system also independently detects and disables specific ASINs that are dragging down your page view ratio.

What is SFP safety inventory?

It’s a pre-configured minimum stock quantity. When an SFP ASIN’s inventory drops below that quantity, the OMS automatically removes it from your SFP shipping templates so it can’t be sold into an order you can’t fulfill.

Where can I learn more about Amazon’s OTDR requirement itself?

Our post on how Amazon’s OTDR policy affects seller rank and visibility covers the requirement in detail. This post focuses specifically on the ShipSage automation tools that help protect it.

The Bottom Line

SFP performance risk doesn’t show up all at once — it accumulates from a slow weekend carrier, a stockout nobody caught in time, or a shipping decision made under time pressure. The ShipSage OMS configuration tools covered here — Buy Shipping automation, OTDR-triggered protection, ASIN auto-disable by size tier, and safety inventory — are built to catch those conditions automatically, using rules you set once rather than decisions you have to remake every day.

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