To delete bulk recordings from Twilio's Recordings API, you can use Python and its built-in libraries. First, set up your environment with Python 3.x, the Twilio helper library, and necessary environment variables. Then, create a script that lists all recordings created before a specified date, extracts their RecordingSID, and deletes them using the Twilio API. However, this approach has limitations, such as waiting for response times from Twilio, which can be time-consuming for large numbers of recordings. To overcome this, use multi-threading to delete recordings concurrently, creating a centralized queue and worker threads that drain it while writing results to a CSV file. Finally, you can modify the script to download recordings to cold storage on magnetic tape if needed.