It's to do with imbd. It shows ads and since Amazon Prime Video integrates IMDb TV content into the same interface, the ads also appear as well. That's what is causing ads mid show. There have always been more subtle ads pre show etc.
How do I get rid of ads on Amazon Prime video? Go to Manage Your Content and Devices. Select Devices, and then select your device. Under Special Offers, click Remove offers. A pop-up window then displays the price to remove ads.
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