If you are currently on :

Because version 1808 represents the jump from Office 2016 to Office 2019, it brought several features that were previously only available to Microsoft 365 subscribers:

Users still on 1808 often report:

Version 1808 (referring to Year 2018, Month 08) was the stable branch used for the initial commercial release of on September 24, 2018.

Unlike Microsoft 365, Version 1808 does include: