Downloadable Product Available Date

I want to sell audio recordings from a weekly recurring event to those who attended that session. Obviously the current week’s recording wouldn’t be available until sometime after the event finishes. I’d like to keep using the same Product and ideally don’t want to have to edit its Downloadable Files week after week. Customers should only be able to download the recording for the session they attended. I see I can expire downloads after a certain number of days following a purchase, but that wouldn’t prevent a customer from purchasing and downloading a recording from a previous session (by accident or on purpose).

Is this possible? If not, does anyone have alternate suggestions?

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