diff --git a/changelog.d/19644.bugfix b/changelog.d/19644.bugfix
new file mode 100644
index 0000000000..73ab4bc63e
--- /dev/null
+++ b/changelog.d/19644.bugfix
@@ -0,0 +1 @@
+Fix long-standing but niche bug with sync where it could attempt to fetch data with flawed invalid future tokens.
diff --git a/changelog.d/19644.misc b/changelog.d/19644.misc
new file mode 100644
index 0000000000..d3a7a12fc3
--- /dev/null
+++ b/changelog.d/19644.misc
@@ -0,0 +1 @@
+Add new `Notifier.wait_for_multi_writer_stream_token(...)` utility to make it easy wait for the worker to catch up to any kind of token.