OP is in the wrong about message contents. Message contents were never compromised to my knowledge. The issue was specifically metadata like login times and IP

OP is in the wrong about message contents. Message contents were never compromised to my knowledge. The issue was specifically metadata like login times and IP addresses. Also possibly mail server logs, such as that a user sent a message to a Gmail account, although I'm not 100% certain on that last point. Once again, when using the proper settings in ProtonMail, the message contents cannot be retrieved without a brute force attack thanks to end-to-end encryption.