Upgrade from older versions (v37)

Hi all.

I just got into a project that is using an older version of wsc library. Can you point me some document that tells about the changes between versions and migration guidelines?

We are currently at version 37.0.3 and we want to go to latest one. One note from the other dev was saying about versions 38+ will now use GMT for all dates, so I believe we will probably face new changes, and I am expecting even class changes.