release.adoc: how to test a staged release

docs/modules/ROOT/pages/release.adoc

@@ -233,6 +233,23 @@ until a "Repository closed" message appears in the progress.
 
 image::sonatype/repo_closed.png[repo_closed.png]
 
+Once the repository is closed, its artifacts become publicly
+visble at SonaType, but they aren't yet synched
+to Maven Central.
+This is your last opportunity to test the proposed release,
+using (for example)
+
+[source,groovy]
+----
+repositories {
+    maven { url 'https://s01.oss.sonatype.org/content/groups/staging' }
+    mavenCentral()
+}
+----
+
+If the staged artifacts don't work for some reason, drop them,
+address the issue(s), and start over with a new release name.
+
 To begin the synching process,
 click on the "Release" button and then the "Confirm" button.
 The process usually takes about 20 minutes.