Pick a release date, write a blurb.

ChangeLog

@@ -1,5 +1,21 @@
-Changes in version 0.4.2.5 - 2019-12-??
-  Blurb blurb.
+Changes in version 0.4.2.5 - 2019-12-09
+  This is the first stable release in the 0.4.2.x series. This series
+  improves reliability and stability, and includes several stability and
+  correctness improvements for onion services. It also fixes many smaller
+  bugs present in previous series.
+
+  Per our support policy, we will support the 0.4.2.x series for nine
+  months, or until three months after the release of a stable 0.4.3.x:
+  whichever is longer. If you need longer-term support, please stick
+  with 0.3.5.x, which will we plan to support until Feb 2022.
+
+  Per our support policy, we will support the 0.4.2.x series for nine
+  months, or until three months after the release of a stable 0.4.3.x:
+  whichever is longer. If you need longer-term support, please stick
+  with 0.3.5.x, which will we plan to support until Feb 2022.
+
+  Below are the changes since 0.4.1.4-rc. For a complete list of changes
+  since 0.4.1.5, see the ReleaseNotes file.
 
   o Minor features (geoip):
     - Update geoip and geoip6 to the December 3 2019 Maxmind GeoLite2

ReleaseNotes

@@ -2,8 +2,19 @@ This document summarizes new features and bugfixes in each stable
 release of Tor. If you want to see more detailed descriptions of the
 changes in each development snapshot, see the ChangeLog file.
 
-Changes in version 0.4.2.5 - 2019-12-??
-  Blurb blurb.
+Changes in version 0.4.2.5 - 2019-12-09
+  This is the first stable release in the 0.4.2.x series. This series
+  improves reliability and stability, and includes several stability and
+  correctness improvements for onion services. It also fixes many smaller
+  bugs present in previous series.
+
+  Per our support policy, we will support the 0.4.2.x series for nine
+  months, or until three months after the release of a stable 0.4.3.x:
+  whichever is longer. If you need longer-term support, please stick
+  with 0.3.5.x, which will we plan to support until Feb 2022.
+
+  Below are the changes since 0.4.1.4-rc. For a complete list of only
+  the changes since 0.4.2.4-rc, see the ChangeLog file.
 
   o Major features (directory authorities):
     - Directory authorities now reject relays running all currently