The Twilio team is introducing a change to the IncomingPhoneNumbers provisioning API on February 12, 2020, requiring regulated phone numbers to include proper documentation for BundleSID/IdentitySID in API calls. This change aims to ensure regulatory compliance across countries and protect customer phone numbers from non-compliance issues. The change will have a brownout period starting January 15, allowing customers to prepare for the new requirement. Customers can use the Compliance Report in Twilio's web Console to determine which phone numbers are missing Regulatory Bundles. Existing API users may need to update their documentation bundles and API calls accordingly.