diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 954fe52..5621554 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -4,7 +4,11 @@ Change Log
 
 This document records all notable changes to `stellar-model <https://github.com/StellarCN/stellar-model/>`_.
 
-0.3.0b0 (Horizon v2.9.0~rc1)
+0.3.1b0
+----------------------------
+* fix: ClaimPredicate.rel_before, Optional[datetime] -> Optional[int]
+
+0.3.0b0
 ----------------------------
 This release contains breaking updates.
 
@@ -12,22 +16,22 @@ You can check the `release log of horizon-v2.9.0-rc1 <https://github.com/stellar
 
 * feat: add support for horizon-v2.9.0~rc1 (`#21 <https://github.com/StellarCN/stellar-model/pull/21/>`_)
 
-0.2.2b0 (Horizon v2.8.3)
+0.2.2b0
 ------------------------
 * fix: make `ClaimableBalance.last_modified_time` and `Offer.last_modified_time` optional.
 
-0.2.1b0 (Horizon v2.8.3)
+0.2.1b0
 ------------------------
 * fix: make `Account.last_modified_time` optional. (`#19 <https://github.com/StellarCN/stellar-model/pull/19/>`_)
 
-0.2.0b0 (Horizon v2.5.2)
+0.2.0b0
 ------------------------
 * feat: add support for muxed account.
 
-0.1.0b1 (Horizon v2.2.0)
+0.1.0b1
 ------------------------
 * Bug fix.
 
-0.1.0b0 (Horizon v2.2.0)
+0.1.0b0
 ------------------------
 * First beta release.
\ No newline at end of file
diff --git a/README.rst b/README.rst
index c2802b7..1d8bac8 100644
--- a/README.rst
+++ b/README.rst
@@ -37,7 +37,7 @@ Please check the list `here <https://github.com/StellarCN/stellar-model/issues/2
 
 .. code-block:: text
 
-    pip install stellar-model==0.3.0b0
+    pip install stellar-model==0.3.1b0
 
 Example
 =======
diff --git a/docs/requirements.txt b/docs/requirements.txt
index b49e1da..229a2df 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1 +1 @@
-stellar-model==0.3.0b0
\ No newline at end of file
+stellar-model==0.3.1b0
\ No newline at end of file
diff --git a/pyproject.toml b/pyproject.toml
index a3ba2fb..933dc34 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "stellar-model"
-version = "0.3.0b0"
+version = "0.3.1b0"
 description = "Parse the raw Stellar data into Python models."
 authors = ["overcat <4catcode@gmail.com>"]
 readme = "README.rst"
diff --git a/stellar_model/__init__.py b/stellar_model/__init__.py
index 377edb5..8d3a19d 100644
--- a/stellar_model/__init__.py
+++ b/stellar_model/__init__.py
@@ -1,5 +1,5 @@
-__version__ = "0.3.0b0"
-__supported_horizon_version__ = "2.8.3"
+__version__ = "0.3.1b0"
+__supported_horizon_version__ = "2.9.0"
 __url__ = "https://github.com/StellarCN/stellar-model"
 __issues__ = f"{__url__}/issues"