This morning we had a sudden flood of tweets for old posts (some very old). There seemed to be no rhyme or reason to it. We hadn't made any recent changes on the site besides deactivating the Find Duplicate plugin (that I used briefly to find and remove duplicated posts) and the posts that were tweeted were seemingly random.
After a minute (and about 40 tweets) it stopped. I have disabled the plugin for now, for fear of it happening again.
Any idea how I can troubleshoot this problem so it doesn't happen again?