This 1.14 build is newer, chronologically, than the latest posted 1.15 build.
But any 1.15 build is "nexter" (if that's a word) than any 1.14 build - so Android won't let you go "backwards".
Mainly the 1.14 "stable + fixes" are for those users who:
1) are running our current official 1.14 from Play
2) ran into a specific issue
3) would like to do a minimal update to just get the fix
In this 1.14.2 this "specific issue" is "double spaced reply headers in Outlook for Windows".
The 1.15-dev builds are for users who:
1) are interested in running latest stuff
2) with new features "in development"
In the current 1.15 builds these "new features" are smart folder in the nav drawer.
The next 1.15-dev will pick up all the bug fixes from the 1.14 series including this one and continue with "the new stuff".
