diff --git a/version.h b/version.h
index ce4fbe66b4..f9b602a0a7 100644
--- a/version.h
+++ b/version.h
@@ -14,8 +14,8 @@
 #define RUBY_PATCHLEVEL -1
 
 #define RUBY_RELEASE_YEAR 2021
-#define RUBY_RELEASE_MONTH 9
-#define RUBY_RELEASE_DAY 30
+#define RUBY_RELEASE_MONTH 10
+#define RUBY_RELEASE_DAY 1
 
 #include "ruby/version.h"