diff --git a/CHANGELOG.md b/CHANGELOG.md
index 275951fc..0edeccc2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,11 @@
 
 ## 1.2
 
+### 1.2.9
+- Fix missing method `mobility_attribute?` on Rails 7
+  ([#582](https://github.com/shioyama/mobility/pull/582) and
+  [#584](https://github.com/shioyama/mobility/pull/584))
+
 ### 1.2.8
 - Fix issues with subclassing, such as when using AR STI,
   fixes [#566](https://github.com/shioyama/mobility/issues/566)
diff --git a/README.md b/README.md
index 445ea981..f97f1b0e 100644
--- a/README.md
+++ b/README.md
@@ -55,7 +55,7 @@ Installation
 Add this line to your application's Gemfile:
 
 ```ruby
-gem 'mobility', '~> 1.2.8'
+gem 'mobility', '~> 1.2.9'
 ```
 
 ### ActiveRecord (Rails)
diff --git a/lib/mobility/version.rb b/lib/mobility/version.rb
index b155ba8f..4a2cdcff 100644
--- a/lib/mobility/version.rb
+++ b/lib/mobility/version.rb
@@ -8,7 +8,7 @@ def self.gem_version
   module VERSION
     MAJOR = 1
     MINOR = 2
-    TINY = 8
+    TINY = 9
     PRE = nil
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")