SDK Upgrade 33 to 34 and Firebase Fix for Android App

I need an experienced Android developer to upgrade my Java-based Android fantasy app from SDK 33 to 34. The app uses Firebase for notifications and integrates with a CodeIgniter backend.

Key tasks:
- Upgrade the app to SDK 34 using Android Studio
- Diagnose and fix Firebase notification issues to ensure compatibility with the updated SDK
- Maintain seamless integration with the CodeIgniter backend

The ideal candidate would be proficient in:
- Java and Android development
- Firebase integration
- CodeIgniter backend connectivity

Please note that while I have not specified current issues with Firebase notifications, the successful candidate may need to investigate and resolve potential issues. The upgrade process will be conducted using Android Studio, which is my preferred IDE.

While additional testing beyond the upgrade isn't pre-scheduled, the ability to conduct unit, user acceptance, and performance testing would be an asset.