The games will still by on your PS3; just expired and not playable. As far as PSN goes, since I have not let my PS+ subscription expire, I am not 100% sure. I don't know how they are represented in your download list - they may show but when you download them they will be expired. It is my understanding once you renew, you will have access to anything you previously downloaded via PS+.
I'm with Jc, I've never let my Subscription expire either, but that's good to know jbp, thanks.
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