> [!NOTE]
> **Note:** This migration may affect you only if the client or integration you use sends audio requests to Dialogflow with the following language tags: `en`, `en-us`, `en-au`, `en-gb`, `en-in`, `de`, `es`, `es-es`, `es-us`, `fr`, `fr-ca`, `fr-fr`, `it`, `ja`, `nl`, `pt-br`.

## Migration status

As of July 2024, no projects have been [automatically migrated](https://docs.cloud.google.com/dialogflow/es/docs/speech-model-migration#automatic). The
automatic migration will remain on hold until further notice (no ETA).

You can continue to use the classic Speech-to-Text models but are encouraged to
[opt in](https://docs.cloud.google.com/dialogflow/es/docs/speech-model-migration#opt-in) to use conformer-based speech models.

## Migration overview

For certain [language tag](https://docs.cloud.google.com/dialogflow/es/docs/reference/language) and speech
setting combinations, the Dialogflow CX and Dialogflow ES traffic with audio will
gradually route away from the classic Speech-to-Text models behind the
`command_and_search`, `default`, `phone_call`, and `video` model identifiers to
the new conformer-based [speech
models](https://docs.cloud.google.com/speech-to-text/docs/transcription-model). As the redirection will be
internal only, the current model identifiers and code will remain valid and
continue to serve traffic.

The tables in the [Migration for `en` and `en-us`language tags](https://docs.cloud.google.com/dialogflow/es/docs/speech-model-migration#en-en-us) and
[Migration for `de`, `en-au`, `en-gb`, `en-in`, `es`, `es-es`, `es-us`, `fr`,
`fr-ca`, `fr-fr`, `it`, `ja`, `nl`, `pt-br` language
tags](https://docs.cloud.google.com/dialogflow/es/docs/speech-model-migration#non-en-en-us-affected) sections show the routing of Speech-to-Text
models that will take place when the migration takes effect. If your
configuration matches the language tag and the first two columns in the table,
the new model identifier is listed in the third column. No change is expected
for other configurations.

See the [Migration options](https://docs.cloud.google.com/dialogflow/es/docs/speech-model-migration#options) section to choose the best option for you.

## Migration for `en` and `en-us` language tags

| Current [`model`](https://docs.cloud.google.com/dialogflow/es/docs/reference/rpc/google.cloud.dialogflow.v2#inputaudioconfig) identifier | Current [`single_utterance`](https://docs.cloud.google.com/dialogflow/es/docs/reference/rpc/google.cloud.dialogflow.v2#inputaudioconfig) setting \* | Model identifier that traffic will be directed to |
|---|---|---|
| `command_and_search` | `false` | `latest_long` |
| `command_and_search` | `true` | `latest_short` |
| `default` | `false` | `telephony` |
| `phone_call` | `false` | `telephony` |
| `phone_call` ([`model_variant`](https://docs.cloud.google.com/dialogflow/es/docs/reference/rpc/google.cloud.dialogflow.v2#inputaudioconfig) is not `USE_STANDARD`) | `true` | `telephony_short` |
| `video` | `false` | `telephony` |
| Unspecified | `true/false` | Model is auto-selected from among the above, based on the parameters in [`InputAudioConfig`](https://docs.cloud.google.com/dialogflow/es/docs/reference/rpc/google.cloud.dialogflow.v2#inputaudioconfig) |

| Symbol | Description |
|---|---|
| \* | If your Dialogflow CX agent has [enabled advanced timeout-based end of speech sensitivity](https://docs.cloud.google.com/dialogflow/cx/docs/concept/agent#advanced-end-of-speech-sensitivity), then the model identifier is routed assuming `single_utterance` is `false`, even if the setting is set to `true` at runtime. |

## Migration for `de`, `en-au`, `en-gb`, `en-in`, `es`, `es-es`, `es-us`, `fr`, `fr-ca`, `fr-fr`, `it`, `ja`, `nl`, `pt-br` language tags

| Current [`model`](https://docs.cloud.google.com/dialogflow/es/docs/reference/rpc/google.cloud.dialogflow.v2#google.cloud.dialogflow.v2.InputAudioConfig.FIELDS.string.google.cloud.dialogflow.v2.InputAudioConfig.model) identifier | Current [`single_utterance`](https://docs.cloud.google.com/dialogflow/es/docs/reference/rpc/google.cloud.dialogflow.v2#google.cloud.dialogflow.v2.InputAudioConfig.FIELDS.bool.google.cloud.dialogflow.v2.InputAudioConfig.single_utterance) setting \* | Model identifier that traffic will be directed to |
|---|---|---|
| `command_and_search` | `false` | `latest_long` |
| `command_and_search` | `true` | `latest_short` |
| `default` | `false` | `latest_long` |
| Unspecified | `true/false` | Model is auto-selected from among the above, based on the parameters in [`InputAudioConfig`](https://docs.cloud.google.com/dialogflow/es/docs/reference/rpc/google.cloud.dialogflow.v2#inputaudioconfig) |

| Symbol | Description |
|---|---|
| \* | If your Dialogflow CX agent has [enabled advanced timeout-based end of speech sensitivity](https://docs.cloud.google.com/dialogflow/cx/docs/concept/agent#advanced-end-of-speech-sensitivity), then the model identifier is routed assuming `single_utterance` is `false`, even if the setting is set to `true` at runtime. |

## Migration options

There are three migration options: early opt-in, automatic, and temporary
opt-out.

### Opt in and migrate earlier

To opt in proactively, change the speech model identifier that you have been
using in the [Dialogflow CX
API](https://docs.cloud.google.com/dialogflow/cx/docs/reference/rest/v3/ConversationTurn#inputaudioconfig)
and [Dialogflow ES
API](https://docs.cloud.google.com/dialogflow/es/docs/reference/rpc/google.cloud.dialogflow.v2#inputaudioconfig)
with the updated one. For Dialogflow CX, you can also change the [model
identifier](https://docs.cloud.google.com/dialogflow/cx/docs/concept/agent#stt-model-selection) in the
**Advanced speech settings** under **Speech and IVR settings** in the
Dialogflow CX console.

Migrating your project proactively gives you time to test the models and take
advantage of the improved accuracy and robustness earlier. This approach is
highly recommended, especially if you are using a model that will route to the
new `telephony` and `telephony_short` models.

If you experience issues with the new models, [open a Google Cloud support
case](https://docs.cloud.google.com/support/docs/customer-care-procedures) with issue details.

### Migrate automatically

> [!NOTE]
> **Note:** See [migration status](https://docs.cloud.google.com/dialogflow/es/docs/speech-model-migration#status).

To be migrated automatically, no action is required on your part. The existing
Speech-to-Text model identifiers are valid and we will shift traffic
internally.

### Opt out and migrate later

Due to the suspended [migration status](https://docs.cloud.google.com/dialogflow/es/docs/speech-model-migration#status), new opt-out requests are not
accepted. If your projects were opted out before July 2024, they will remain in
this state until further announcement.