> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nadles.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Modifying products

As a general rule, changes in products don't affect existing subscriptions.

However, there are several exceptions.

## Adding and removing endpoints

When you add a new endpoint to the product or remove an existing one, the following rules apply:

* If an endpoint is added to a product, it appears in existing subscriptions to that product too.

* If this endpoint is then deleted, it gets deleted from the existing subscriptions too.

* Endpoints added to a product before a subscription is created remain part of the subscription even if the endpoint is later deleted from the product.

* If a new endpoint is added to a billable metric, it is also added to the same billable metric in subscriptions.

* If an existing endpoint is removed from a billable metric, it doesn't get removed from the same billable metric in subscriptions.

## Adding and removing billable metrics

* If you add new billable metrics/rate limits to the product, they don't appear in the existing subscriptions.

* If you delete a billable metric from the product, it doesn't get deleted from existing subscriptions.

## Subscription upgrades/downgrades

Whenever you modify the [Allow switching to following products](/products/create#allow-switching-to-following-products) config of a product, it has effect on existing subscriptions.