diff --git a/doc/Type/DateTime.rakudoc b/doc/Type/DateTime.rakudoc
index 5676e99ba..29ee88f2e 100644
--- a/doc/Type/DateTime.rakudoc
+++ b/doc/Type/DateTime.rakudoc
@@ -246,6 +246,8 @@ Available as of release 2023.02 of the Rakudo compiler.
 
     multi method Numeric(DateTime:D: --> Instant:D)
 
+Available as of the 2021.09 release of the Rakudo compiler.
+
 Converts the invocant to L«C<Instant>|/type/Instant».  The same value can
 be obtained with the C<Instant> method.  This allows C<DateTime> objects
 to be used directly in arithmetic operations.