Upon expiry, you are no longer a member of the Apple Developer Program and any apps you had on the App Store or Mac App Store are no longer available. But they are still there and you can reinstate them on renewal.
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If your membership has already expired when you renew, your renewal will activate once you complete the renewal process and any free apps you had available for download will become available again within 24 hours. Any paid apps you had available for download will become available again after you sign in to iTunes Connect and complete your Paid Applications contract. You do not need to resubmit your apps.