Which version of Office 2016 I have?
Solution 1:
This is the same version, distributed on two channels with a difference of several days between the two.
The first was the Office Insider Monthly (Targeted) v1802 build 9029.2106 from Feb. 20.
The second was the Office 2016 & Office 365 Monthly Channel v1802 build 9029.2167 from Feb. 26.
The Insider version predates the Monthly version by almost one week.
What we have here is an amusing gaff by the Office developers. The version number was entered correctly as the Monthly one in the About Word title, but in the dialog called up by that button it remained the Insider version.
In the official Microsoft Update history for Office 365 ProPlus (listed by date), there is only mentioned the Monthly version, since the Insider version is not an official release.
Solution 2:
One is the original version, the other is the update version (channel). Please refer to this article: https://social.technet.microsoft.com/Forums/en-US/a86b9b5a-47b1-4e7d-8759-dc0e4282369c/how-to-decode-office-365-proplus-buildversion-numbers?forum=Office2016ITPro
Please correct me if any errors in my answer.