diff --git a/acstore/__init__.py b/acstore/__init__.py
index 523f88a..0cee674 100644
--- a/acstore/__init__.py
+++ b/acstore/__init__.py
@@ -5,4 +5,4 @@
 to read and write plaso storage files.
 """
 
-__version__ = '20240406'
+__version__ = '20240407'
diff --git a/acstore/helpers/json_serializer.py b/acstore/helpers/json_serializer.py
index 2632aad..84ba1ca 100644
--- a/acstore/helpers/json_serializer.py
+++ b/acstore/helpers/json_serializer.py
@@ -1,6 +1,7 @@
 # -*- coding: utf-8 -*-
 """Attribute container JSON serializer."""
 
+from acstore.containers import interface as containers_interface
 from acstore.containers import manager as containers_manager
 from acstore.helpers import schema as schema_helper
 
@@ -45,11 +46,14 @@ def ConvertAttributeContainerToJSON(cls, attribute_container):
 
     for attribute_name, attribute_value in attribute_container.GetAttributes():
       data_type = schema.get(attribute_name, None)
-      serializer = schema_helper.SchemaHelper.GetAttributeSerializer(
-          data_type, 'json')
-
-      if serializer:
-        attribute_value = serializer.SerializeValue(attribute_value)
+      if data_type == 'AttributeContainerIdentifier' and isinstance(
+          attribute_value, containers_interface.AttributeContainerIdentifier):
+        attribute_value = attribute_value.CopyToString()
+      else:
+        serializer = schema_helper.SchemaHelper.GetAttributeSerializer(
+            data_type, 'json')
+        if serializer:
+          attribute_value = serializer.SerializeValue(attribute_value)
 
       # JSON will not serialize certain runtime types like set, therefore
       # these are cast to list first.
@@ -104,11 +108,15 @@ def ConvertJSONToAttributeContainer(cls, json_dict):
         continue
 
       data_type = schema.get(attribute_name, None)
-      serializer = schema_helper.SchemaHelper.GetAttributeSerializer(
-          data_type, 'json')
-
-      if serializer:
-        attribute_value = serializer.DeserializeValue(attribute_value)
+      if data_type == 'AttributeContainerIdentifier':
+        identifier = containers_interface.AttributeContainerIdentifier()
+        identifier.CopyFromString(attribute_value)
+        attribute_value = identifier
+      else:
+        serializer = schema_helper.SchemaHelper.GetAttributeSerializer(
+            data_type, 'json')
+        if serializer:
+          attribute_value = serializer.DeserializeValue(attribute_value)
 
       setattr(attribute_container, attribute_name, attribute_value)
 
diff --git a/acstore/sqlite_store.py b/acstore/sqlite_store.py
index 6891de6..9289ebe 100644
--- a/acstore/sqlite_store.py
+++ b/acstore/sqlite_store.py
@@ -180,23 +180,15 @@ class SQLiteAttributeContainerStore(
 
   # The earliest format version, stored in-file, that this class
   # is able to append (write).
-  _APPEND_COMPATIBLE_FORMAT_VERSION = 20221023
+  _APPEND_COMPATIBLE_FORMAT_VERSION = 20230312
 
   # The earliest format version, stored in-file, that this class
   # is able to upgrade (write new format features).
-  _UPGRADE_COMPATIBLE_FORMAT_VERSION = 20221023
+  _UPGRADE_COMPATIBLE_FORMAT_VERSION = 20230312
 
   # The earliest format version, stored in-file, that this class
   # is able to read.
-  _READ_COMPATIBLE_FORMAT_VERSION = 20221023
-
-  # TODO: kept for backwards compatibility.
-  _CONTAINER_SCHEMA_TO_SQLITE_TYPE_MAPPINGS = {
-      'AttributeContainerIdentifier': 'TEXT',
-      'bool': 'INTEGER',
-      'int': 'INTEGER',
-      'str': 'TEXT',
-      'timestamp': 'BIGINT'}
+  _READ_COMPATIBLE_FORMAT_VERSION = 20230312
 
   _CREATE_METADATA_TABLE_QUERY = (
       'CREATE TABLE metadata (key TEXT, value TEXT);')
diff --git a/config/dpkg/changelog b/config/dpkg/changelog
index 71fbb16..f39bce2 100644
--- a/config/dpkg/changelog
+++ b/config/dpkg/changelog
@@ -1,5 +1,5 @@
-acstore (20240406-1) unstable; urgency=low
+acstore (20240407-1) unstable; urgency=low
 
   * Auto-generated
 
- -- Log2Timeline maintainers <log2timeline-maintainers@googlegroups.com>  Sat, 06 Apr 2024 05:54:23 +0200
+ -- Log2Timeline maintainers <log2timeline-maintainers@googlegroups.com>  Sun, 07 Apr 2024 07:12:15 +0200
diff --git a/setup.cfg b/setup.cfg
index 59b1cfb..3533d9c 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,6 +1,6 @@
 [metadata]
 name = acstore
-version = 20240406
+version = 20240407
 description = Attribute Container Storage (ACStore).
 long_description = ACStore, or Attribute Container Storage, provides a stand-alone implementation to read and write attribute container storage files.
 long_description_content_type = text/plain