Encryption / Privacy when using API (both whisper and chat completion)

I connect to OpenAI Whisper using API and have had good results transcribing audio files. OpenAI in their FAQ say data obtained through API is not used for training models, unless user opted in. However, is the audio file saved on their servers ? If so, is their an API or process to request to delete those files.

Similarly, when using Chat Completions, to get a summary of the transcription or other prompts, also via API, does OpenAI store such queries for later use by their employees ?

Lastly, are we able to encrypt data. Is OpenAI able to summarize or transcribe homomorphic encrypted files ?

Thank you for any pointers with respect to these questions.

See Data Usage Policy. Data is stored for 30 days. You have no visibility or control into this.