Hello @Jonatan Perales , Thanks for using Microsoft Q&A Platform.
Sorry to hear about the inconveniences that has caused.
We will definitely share this feedback with the product team regarding the checkbox performance for API version (3.1 General). Try with the 2023-10-31-preview version to see if that helps.
Regarding your question about extending/ upgrading the existing model, you can select the project and choose upgrade
option as shown here. You can upgrade the API version with this feature.
I hope this helps. If you still face issue, please raise support ticket in the Azure portal.
Regards,
Vasavi
-Please kindly accept the answer and vote 'yes' if you feel helpful to support the community, thanks.