README.md in erp_integration-0.55.0 vs README.md in erp_integration-0.56.0

@@ -42,13 +42,16 @@
 ### API keys rotation
 
 To set up API key rotation, configure multiple keys.
 Every time a Fulfil client receives a `404` or `429`, it will rotate an API key.
 
+You can set the `api_key_rotation_threshold` option to automatically change the API key when requests are running low. If you don't want to use the `x-ratelimit-remaining` response header for rotation, set the `api_key_rotation_threshold` to 0 or ignore it. The minimum threshold is 1, meaning the key will rotate when there are 0 remaining requests.
+
 ```erb
 # config/initializers/erp_integration.rb
 ErpIntegration.configure do |config|
   config.fulfil_api_keys = ['<your-api-key1>', '<your-api-key2>']
+  config.api_key_rotation_threshold = 1
   ...
 end
 ```
 
 You can also configure a separate group of API keys for each resource.