Release notes for 6.0.0-dev1 (#6542)

CHANGELOG.md

@@ -5,6 +5,15 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [6.0.0-dev1]
+
+[6.0.0-dev1]: https://github.com/microsoft/CCF/releases/tag/6.0.0-dev1
+
+### Changed
+
+- Output of `ccf::describe_merkle_proof_v1(receipt)` has been updated, and is now described by [ccf-tree-alg schema](https://github.com/microsoft/CCF/blob/main/cddl/ccf-tree-alg.cddl).
+- Improved error message when attempting to obtain receipts for a past epoch during a recovery (#6507).
+
 ## [6.0.0-dev0]
 
 [6.0.0-dev0]: https://github.com/microsoft/CCF/releases/tag/6.0.0-dev0