Exchange Server TLS guidance Part 2: Enabling TLS 1.2 and Identifying Clients Not Using It

Note: There is one known exception to the message headers example. When a client sends a message by connecting to a server using authenticated SMTP (also known as the SMTP client submission protocol), the TLS version in the messages headers does not show the correct TLS version used by a customer’s client or device. Microsoft is investigating the possibility of adding this information in a future update.

Is this still the case?

My header is showing;

Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384)

I am suspecting this is being displayed only because of the Exchange sever sending the message, and not the actual connection between the client and the SMTP server. Is there any way for me to figure out what version the client is using to connect to o365 smtp?