Depends on how much link juice is flowing to each page.
Your homepage likely has more link juice and can be fixed withing 24-28 hours. Your deep pages probably have much less link juice and thus are only crawled once a week or even less frequently. So it will take much longer for those pages to bounce back.
Let me refer you to a similar problem that somebody posted about last week: [webmasterworld.com...] I have experience with two such mistakes and SEOMoz did an experiment on a blog that did the exact same thing have done.
In all cases, mistakes like this can be disastrous. Expect to recover half the traffic that you have lost, but the rest is going to take months to come back.