diff --git a/ouroboros-consensus-cardano/changelog.d/20241218_095046_nick.frisby_annotate_headers_with_time.md b/ouroboros-consensus-cardano/changelog.d/20241218_095046_nick.frisby_annotate_headers_with_time.md
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+++ b/ouroboros-consensus-cardano/changelog.d/20241218_095046_nick.frisby_annotate_headers_with_time.md
@@ -0,0 +1,23 @@
+<!--
+A new scriv changelog fragment.
+
+Uncomment the section that is right (remove the HTML comment wrapper).
+-->
+
+<!--
+### Patch
+
+- A bullet item for the Patch category.
+
+-->
+<!--
+### Non-Breaking
+
+- A bullet item for the Non-Breaking category.
+
+-->
+
+### Breaking
+
+- Update now that `ImmutableEraParams` was split out
+
diff --git a/ouroboros-consensus-diffusion/changelog.d/20241218_095040_nick.frisby_annotate_headers_with_time.md b/ouroboros-consensus-diffusion/changelog.d/20241218_095040_nick.frisby_annotate_headers_with_time.md
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+++ b/ouroboros-consensus-diffusion/changelog.d/20241218_095040_nick.frisby_annotate_headers_with_time.md
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+<!--
+A new scriv changelog fragment.
+
+Uncomment the section that is right (remove the HTML comment wrapper).
+-->
+
+<!--
+### Patch
+
+- A bullet item for the Patch category.
+
+-->
+<!--
+### Non-Breaking
+
+- A bullet item for the Non-Breaking category.
+
+-->
+
+### Breaking
+
+- Use `HeaderWithTime` for the ChainSync candidates
diff --git a/ouroboros-consensus/changelog.d/20241218_095010_nick.frisby_annotate_headers_with_time.md b/ouroboros-consensus/changelog.d/20241218_095010_nick.frisby_annotate_headers_with_time.md
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+++ b/ouroboros-consensus/changelog.d/20241218_095010_nick.frisby_annotate_headers_with_time.md
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+<!--
+A new scriv changelog fragment.
+
+Uncomment the section that is right (remove the HTML comment wrapper).
+-->
+
+<!--
+### Patch
+
+- A bullet item for the Patch category.
+
+-->
+
+### Non-Breaking
+
+- Maintain a parallel selection with time annotations since the
+  `ConsensusBlockFetch` interface uses the same type argument for ChainSync
+  candidates and the current selection.
+
+### Breaking
+
+- Define `HeaderWithTime`.
+
+- Use `HeaderWithTime` for the ChainSync candidates.
+
+- Split out `ImmutableEraParams` so that the test blocks don't have to
+  instantiate the `SingleEraBlock` omnibus.
+
+- Remove the `NoThunks Bimap` orphan instance (it's now upstream in the `resource-registry` library).