diff --git a/CHANGELOG.md b/CHANGELOG.md
index f827a47..1ab03f4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,11 @@
 
 All notable changes to the [ChatGPT](https://marketplace.visualstudio.com/items?itemName=genieai.chatgpt-vscode) extension will be documented in this file.
 
+## [V0.0.12] 🌞 Custom system message & o1-mini and o1-preview models - 2024-09-13
+
+- Added a new setting to customize the system message / context that starts your conversation with the AI.
+- You can now use o1-mini and o1-preview models. **Please note that these new models have usage tier limitations. See [Usage tiers](https://platform.openai.com/docs/guides/rate-limits/usage-tiers).**
+
 ## [V0.0.11] GPT-4o and 2024 model updates - Revive Editor View - 2024-06-14
 
 - Use 2024 OpenAI models including `gpt-4o`, `gpt-4o-2024-05-13`, `gpt-4-turbo`, `gpt-4-turbo-2024`, `gpt-4-turbo-preview`, `gpt-4-0125-preview`
diff --git a/README.md b/README.md
index 37a5eb1..5116766 100644
--- a/README.md
+++ b/README.md
@@ -42,6 +42,15 @@
 
 # 📣 What's new?
 
+<details open>
+  <summary><strong> 🌞 Custom system message & o1-mini and o1-preview models</strong></summary>
+
+- Added a new setting to customize the system message / context that starts your conversation with the AI.
+- Update the `genieai.systemMessage` setting to customize your system message.
+- You can now use o1-mini and o1-preview models. **Please note that these new models have usage tier limitations. See [Usage tiers](https://platform.openai.com/docs/guides/rate-limits/usage-tiers).**
+
+</details>
+
 <details open>
   <summary><strong> ⏫ GPT-4o & 2024 Models available</strong></summary>
 
@@ -53,7 +62,7 @@
 
 </details>
 
-<details open>
+<details>
   <summary><strong> ⚡ Generate commit messages functionality added</strong></summary>
 
 - Generate commit messages right within VS Code: