Before you start
By default, Availability rule is set to No restriction. Until you change it, customers can add or swap in any product regardless of its billing interval.
You can choose one rule at a time. Filter by interval hides mismatched products entirely, while Auto-split on mismatch shows them and creates a new subscription when a customer adds one.
This setting affects both the add product and swap product flows in the Customer Portal.
What are interval matching and auto-split?
By default, the Customer Portal doesn't check billing intervals when a customer browses products to add or swap. A customer on a monthly subscription can see and add a product that's only sold on a quarterly selling plan — a configuration that determines how a product is sold on a subscription, including its price and billing frequency. When that happens, the product bills at the monthly frequency instead of the quarterly cadence it was set up for, which can lead to incorrect billing, product misuse, and support tickets.
The Availability rule setting gives you three ways to handle this:
No restriction: Customers can add or swap in any product, regardless of its interval. This is the default.
Filter by interval: Only shows customers products that have a selling plan matching their current subscription's billing interval. Mismatched products are hidden from the add/swap flow entirely.
Auto-split on mismatch: Shows customers all eligible products, regardless of interval. If a customer adds or swaps in a product with a different interval, Skio automatically creates a separate subscription for it at the correct cadence, instead of adding it to the existing subscription.
How to set up interval matching or auto-split
Step 1: Navigate to Portal Settings
In the left-hand menu of your Skio Dashboard, go to Storefront > Portal Settings. Under Subscription rules, find the Product availability card.
Step 2: Choose an availability rule
Open the Availability rule dropdown and select No restriction, Filter by interval, or Auto-split on mismatch.
If you selected Auto-split on mismatch, set the two additional toggles. See Advanced options for auto-split.
Click Save in the Unsaved changes bar.
The Product availability card in Portal Settings.
Advanced options for auto-split
When Auto-split on mismatch is selected, two additional toggles control what the new subscription inherits from the original.
Carry over the cycle count
Controls whether the new subscription starts at cycle 1 or picks up the original subscription's cycle count.
Off: The new subscription is treated as brand new and starts at cycle 1.
On: The new subscription inherits the original subscription's cycle count.
For example, a customer has a monthly subscription on cycle 3 and adds a product that only sells on a 2-week cadence. With this toggle off, the new 2-week subscription starts at cycle 1. With it on, the new subscription also starts at cycle 3, preserving tenure-based progress like Surprise & Delight milestones.
Transfer discount codes
When enabled, Skio attempts to apply the same discount code from the original subscription to the new one. If the discount code has a usage limit and has already been fully redeemed, it won't be applied, and the customer sees a note that their discount code couldn't be applied to the new subscription. When this toggle is off, no discount transfer is attempted.
What customers see
When Filter by interval is selected
Customers only see products with a selling plan matching their subscription's billing interval when they open the add or swap flow. If every available product is filtered out, customers see a message instead of an empty list: "No products are available for your current delivery schedule."
When Auto-split on mismatch is selected
Customers can see and select any eligible product, regardless of interval. If they add or swap in a product with a mismatched interval, a confirmation modal appears before the change goes through:

The confirmation modal shown when a product will trigger a subscription split.
The modal tells the customer their current subscription will continue as-is and that they'll receive a separate shipment for the new product. If they confirm, Skio creates a new subscription at the correct interval, and the customer now sees two subscriptions in their portal.
FAQ
What happens to a prepaid subscription when it gets split?
The new subscription is created as pay-as-you-go, not prepaid, regardless of how the original subscription is billed.
Will changing the availability rule affect subscribers who already have mismatched products?
No. There are no retroactive changes to existing subscriptions. Customers will simply see fewer or more products the next time they open the add or swap flow, depending on which rule you choose.
Can auto-split increase shipping costs for customers?
Yes. Since the new subscription ships separately from the original, a customer could end up with two shipments instead of one. The confirmation modal calls this out before the customer confirms the change.