G. Christopher prefers The Better Man has an earlier placement but also notes it was intended as 2 years after TMP. The year is not stated in the book so I left it where the Pocket Timeline placed it which is around 2 years after TMP.
Actually the year is established pretty unambiguously in TBM. The story explicitly states that McCoy was on Empyrea in 2254, and he's suspected of being the father of a young woman who's just turned 18. Those dates are mentioned specifically and repeatedly in the text. Allowing for 9 extra months, that pretty much pegs the book as falling in 2273. (There are some references to the visit being 20 years earlier, but those are alongside numerous references to it being 18 years, so I assume there's some rounding going on.)
And the bit about coming 2 years after TMP is really only mentioned in the historian's note; it has no relevance to the text proper. The author's intent is that the book takes place between 18 and 20 years after 2254, i.e. roughly 2273.
The Better Man introduces the new Starfleet uniforms. Their color is never stated but the fact that they include a jacket is mentioned repeatedly.
I only find two mentions of a uniform jacket in a Google Books search of the text. They're easy enough to ignore.
Heck, the TMP uniforms had so many variant styles that maybe there was a jacketed version we didn't see in the movie. We know they had those tan field jackets they used when they left the ship, at least.