WhatsApp BSUID Format in Conversations and Webhook Fields

MessagingBinding.Address and Author fields in Conversations webhooks can now contain BSUID-format values (whatsapp:US.ABC123XYZ) in addition to phone-format values (whatsapp:+15551234567). The value returned depends on your contact-book configuration and your history with the end consumer. Conversations webhooks do not use the From or ExternalUserIdentifier fields found in Programmable Messaging. Any code that reads MessagingBinding.Address or Author and assumes phone-number format should be updated to handle both shapes.