Incompatible recorded workflow versions now block embedded replay while preserving the original run, history and completed work. Restore a compatible workflow definition, then explicitly repair the run to continue with a new fenced attempt without repeating completed activities.
The exception remains catchable as VersionNotSupportedException; ordinary application exceptions keep their existing behavior. Version-marker payloads and SDK wire contracts are unchanged. Runs already closed by older versions remain closed.
Source repair and release preparation: #749, #750. Qualification and affected consumer updates are tracked in #744. Exact published-package verification follows this tag; pinned Server images require a rebuilt release to receive the library fix.