Insider level Version Current Build Release Date
Monthly Channel (Targeted)
(formerly Insider Slow)
1712 8827.2082 December 18, 2017

Version Build Release Date Description
1711 8827.2082 December 18, 2017 Contains fixes and improvements for Version 1711. For features, see What's new for Office Insiders.

Source: Update history for Office Insider for Windows desktop - Office Support

See also: Announcing December Monthly Channel update for - Microsoft Community