Difference between UVM 2017-1.0 Reference Implementation and UVM-2017 v0.9 Library Code for IEEE 1800.2

what is the difference between these UVM 2017-1.0 Reference Implementation and UVM-2017 v0.9 Library Code for IEEE 1800.2 when I visit this link
UVM Cookbook Page

In reply to NaveenReddy:

The v0.9 was essentially a release candidate. You can ignore it, or you can diff the source.