We’ve tightened up the messaging experience to make it more consistent and reliable. Guide no longer allows users to send Guide post messages to candidates who don’t have an email address on file, since those messages couldn’t be delivered correctly.

Along with this, the Send availability request flow has been aligned with all other “send message” flows — the recipient is now always the candidate’s primary email, and the To field is no longer selectable. This removes ambiguity, fixes edge cases where messaging silently failed, and ensures a more predictable experience across all candidate communications.