Image cache clear?

Hi, I have a new site where the image names are algorithmic (same file names), but occasionally need to be replaced with a new image at the same url. I understand that while using Jetpack’s image accelerator, the cache won’t clear on them right away. That’s fine.

For instance, I replaced this image on Tuesday. On Friday, the cache hasn’t cleared yet: https://bullpenbobbles.com/abraham-lincoln-washington-nationals-8-18-2007/

How long should it take to update? A week? Month? Is there a way for me to clear it manually?

Any advice is appreciated. Thanks much.

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