Call recordings for a phone sales team

Your company's 250 sales reps call customers through a cloud phone provider, which records every call. Reps start every call from the customer's page in your CRM, the app where they keep notes, so each call belongs to a customer. Managers want to play any call from that page.

The provider keeps a recording for 7 days, then deletes it. Its API can list a day's calls and fetch any recording by call ID. When a recording is ready, the provider also calls your webhook with the call ID and a download link. A few webhook deliveries fail each week.

Each rep makes about 50 calls a working day, 5 days a week, 5 minutes long on average. Recordings are MP3 files at 32 kbps (kilobits a second). The company keeps recordings for 2 years. A customer can ask for their recordings to be deleted, and that must happen within 30 days.

How does every recording reach your storage before the provider deletes it, and what happens when a manager presses Play?