Sophos Phish Threat - Report Message - Support for Exchange 2016?

Are there any plans to support the Report Message/Phish Threat Outlook Add-On for Exchange 2016? Or a potential release date?

We have a go live date already set for our phishing campaign, and this button was a feature we thought was pretty important to have operational by then. We were hoping to have some sort of estimation so we can prepare accordingly. We had a case open with support as the button does appear in Outlook 2016 (Exchange 2016 environment) but it does not function for non-Sophos emails, which has been closed due to "Exchange 2013 on-premise and non-Microsoft mail providers (such as Gmail or other POP/IMAP accounts) are not supported. We are currently working on the support for Exchange 2016 and Exchange 2019."

Thank you!