There's no such thing as Google finishing ranking a site.
Normally, when a webmaster makes a boo-boo that has seemed to affected crawling or ranking, it goes back to normal in a couple of weeks. I've even had a situation when I make on-site improvements and the rankings suffer temporarily, but then they bounce back in a few weeks.
Have you confirmed that Google even noticed your mistake? Did you have HTML Improvement suggestions in your GWT (duplicate meta)?
Am I right to assume we're talking about a brand-new site?
I had about 25 similar pages of each page ( duplicate ) of my site. The thing to consider is that when the boo-boo happened google had not set its final ranking, we were in the spam indexing patent of google ( meaning when there are majors daily ranking varations due to major changes ).
Knowing that,once the boo boo is fixed are we going to start the spam indexing process again or is google going ro re- rank us faster ?