diff --git a/CHANGELOG.md b/CHANGELOG.md
index f8b4f0c8e..8d25bbc44 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,20 @@ Redisson Releases History
 
 Сonsider __[Redisson PRO](https://redisson.pro)__ version for advanced features and support by SLA.
 
+### 20-Apr-2021 - 3.15.4 released
+
+Feature - sslProtocols setting added  
+Feature - nameMapper setting added  
+Feature - `getSigned()`, `setSigned()`, `incrementAndGetSigned()`, `getUnsigned()`, `setUnsigned()`, `incrementAndGetUnsigned()` methods added to `RBitSet` object  
+Feature - `updateEntryExpiration()`, `getWithTTLOnly()` methods added to `RMapCache` object  
+
+Improvement - Spring Cache, MyBatis Cache, Hibernate Cache implementations should read data from Redis slave if idleTime and cache size weren't specified  
+
+Fixed - `ClusterConnectionManager.upDownSlaves()` method throws `ConcurrentModificationException`  
+Fixed - `ClusterConnectionManager.checkMasterNodesChange()` method throws NPE  
+Fixed - `JCache` `CacheEntryUpdatedListener` doesn't get old value of changed entry (thanks to @testower)  
+
+
 ### 30-Mar-2021 - 3.15.3 released
 
 Feature - [connectionListener](https://github.com/redisson/redisson/wiki/2.-Configuration#connectionlistener) setting added  
diff --git a/README.md b/README.md
index c2ea230c8..e12fc53c8 100644
--- a/README.md
+++ b/README.md
@@ -102,14 +102,14 @@ Used by
     <dependency>
        <groupId>org.redisson</groupId>
        <artifactId>redisson</artifactId>
-       <version>3.15.3</version>
+       <version>3.15.4</version>
     </dependency>  
 
 #### Gradle
-    compile 'org.redisson:redisson:3.15.3'  
+    compile 'org.redisson:redisson:3.15.4'  
 
 #### SBT
-    libraryDependencies += "org.redisson" % "redisson" % "3.15.3"
+    libraryDependencies += "org.redisson" % "redisson" % "3.15.4"
 
 #### Java
 
@@ -167,8 +167,8 @@ Consider __[Redisson PRO](https://redisson.pro)__ version for advanced features
 
 ## Downloads
    
-[Redisson 3.15.3](https://repository.sonatype.org/service/local/artifact/maven/redirect?r=central-proxy&g=org.redisson&a=redisson&v=3.15.3&e=jar),
-[Redisson node 3.15.3](https://repository.sonatype.org/service/local/artifact/maven/redirect?r=central-proxy&g=org.redisson&a=redisson-all&v=3.15.3&e=jar)  
+[Redisson 3.15.4](https://repository.sonatype.org/service/local/artifact/maven/redirect?r=central-proxy&g=org.redisson&a=redisson&v=3.15.4&e=jar),
+[Redisson node 3.15.4](https://repository.sonatype.org/service/local/artifact/maven/redirect?r=central-proxy&g=org.redisson&a=redisson-all&v=3.15.4&e=jar)  
 
 ## FAQs
 
diff --git a/redisson/src/main/java/org/redisson/jcache/JCacheEventCodec.java b/redisson/src/main/java/org/redisson/jcache/JCacheEventCodec.java
index 9a2161b66..c2be73e70 100644
--- a/redisson/src/main/java/org/redisson/jcache/JCacheEventCodec.java
+++ b/redisson/src/main/java/org/redisson/jcache/JCacheEventCodec.java
@@ -55,6 +55,7 @@ public class JCacheEventCodec extends BaseEventCodec {
                     buf.readShortLE();
                     result.add(null);
                 }
+                copy.release();
             }
             
             if (sync) {