Since Summertime Saga does not use a standard decimal versioning system that would result in a version number like 0.2016 (versions typically follow formats like 0.20.x, 0.21.x, etc.), it is highly likely you are looking for the changelog for the v0.20.16 update (a popular legacy update) or you may have a typo in the version year.

Fixed issues with audio overlapping during certain cutscenes.

1. Go to the official Summertime Saga website (search “Summertime Saga official”).
2. Look for the Downloads section → Windows version.
3. The changelog is usually displayed on the download page or inside the downloaded .zip file as changelog.txt.

Review: Summertime Saga 0.02016 (Windows, Free)

Summertime Saga’s 0.02016 update pushes the long-running visual novel into sharper territory: more polish, more personality, and a steady march toward the kind of community-driven depth that keeps players coming back. If you like slice-of-life storytelling with a heavy dash of teenage mischief and a sandbox-like progression system, this patch is another solid waypoint.

You're looking for information related to Summertime Saga, a popular adult visual novel game. Specifically, you're interested in the 2016 changelog for the Windows version of the game, which was released for free.