Compatibility, Deprecation, and Migration Plan

The compatibility plan is explored in proposed changes. We will backport this to all minor 3.X versions: 3.0.3, 3.1.3, 3.2.4, 3.3.3, and 3.4.1 . Downgrades to lower versions will be incompatible and will be explicitly stated in future release notes when new fields/records are introduced.