Since the end of April my site quickly dropped out of search-pages that once appeared on the first page went missing, impressions dropped, search traffic dropped, crawl errors have increased and overall traffic has dropped terribly. Apparently something caused the robots.txt file to prevent Google from crawling but as of this morning I was also notified that on the data base the last build for the site map was April 24, 2012. I'm not sure why this happened because when I look into the settings for the plugin the rebuild appears to have made changes successfully. I noticed there was an update done on April 24 and I am assuming something went terribly wrong when the plugin was updated.
Could someone please provide insight? I went as far as sending a site reconsideration to Google and they since have replied stating there was no manual site penalization.
Please note I haven't a clue when it comes to code etc I hire a developer for everything including updates. If at all possible when you are providing advice could you term in a way that I will understand, thank you.