How long does it take for traffic to bounce back from and accidental robots.txt disallow of root?

[bheard]

We accidentally uploaded a robots.txt disallow root for all agents last Tuesday and did not catch the error until yesterday.. so 6 days total of exposure. Organic traffic is down 20%. Google has since indexed the correct version of the robots.txt file. However, we're still seeing awful titles/descriptions in the SERPs and traffic is not coming back. GWT shows that not many pages were actually removed from the index but we're still seeing drastic rankings decreases.

Anyone been through this? Any sort of timeline for a recovery?

Much appreciated!

[EricaMcGillivray]

I'd give it a month before you'll see that bounce back. I wouldn't expect the same rankings as before as Google will be reevaluating your pages, but you should have a pick up in traffic.