We are currently using a reCAPTCHA v3 Classic key for form submissions in our application. As per Google's recommendation, we are planning to migrate this key to the Google Cloud Platform (GCP).

Before proceeding, we would like to clarify the following questions:

1. Our current implementation references the script:
   https://www.google.com/recaptcha/api.js
   After migrating the Classic key to GCP, is it mandatory to update this reference to:
   https://www.google.com/recaptcha/enterprise.js?
2. If we continue using the existing api.js reference after the migration, will the integration remain functional?
3. Will the existing site key value change after migration? Or will the same key continue to be used?
4. Will there be any change in the format or structure of the key itself (e.g., length, prefix) after the migration to GCP?