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1. **Voice Fallback Plan**: You can now define a `fallbackPlan` in your assistant's voice settings in `assistant.voice.fallbackPlan` or `call.squad.members.assistant.voice.fallbackPlan` to specify alternative voices if your primary voice provider fails.

2. **AssemblyAI Credential Management**: You can now specify your AssemblyAI API keys in the updated "Transcriber Providers" page. Create your API key in the [AssemblyAI dashboard](https://www.assemblyai.com/app/account). AssemblyAI errors are now surfaced in the `endedReason` of `Call`, `ServerMessageEndOfCallReport`, and `ServerMessageStatusUpdate`.

![](/_fern-img/227c17bc22bec378b02ddd6b1a72d348650e46fa8a00696c8dc7d6e09d909e55.webp)

3. **Enhanced BYO SIP Trunk Configuration**: When configuring BYO SIP trunk credentials, you can now specify a `techPrefix` for outbound SIP calls and enable `sipDiversionHeader` for authenticating the calling number (if supported). Refer to the `ByoSipTrunkCredential` schema in the [API reference](https://api.vapi.ai/api) to learn more.

![](/_fern-img/66f53b5883940fa75cc2d72070a43fa00f0edc26e6bdac88ec6c101e239e30a6.webp)

4. **File Name Length Constraints**: The maximum file `name` length has been reduced from 100 to 40 characters. The required minimum length is still 1 character.

5. **Increased Server Timeout Limit**: The maximum value of `server.timeoutSeconds` has increased from 60 to 120 seconds, allowing longer timeouts for server responses.

6. **Extended Delay for Tool Messages**: The `timingMilliseconds` maximum in `ToolMessageDelayed` has increased from 20,000 to 120,000 milliseconds, enabling a longer delay for tool messages.