anyone know what this build does? it only has a 3 build number difference but close to 400 files were changed
It was a bugfix for the lobby. Ignore the changed file count, as all the models have different checksums each build, as a byproduct of the build process.
That's nice. I have to download the entire 597 MiB bz2 file every time there is an update. You Maccies and your fancy launcher.
On Windows it's only about 16 or so MB, including re-downloading all the blueprints (since I use the JSON re-formatter: https://forums.uberent.com/threads/reformat-your-json-files.47529/) Edit: Ouch at having to download ~600MB!
If it's any comfort, the full image was getting well over 600MiB. I'm pretty sure those 7 packages were more than 16MiB though (the earlier one was 200), so I'm also jealous of windows.