The FAQ says: "If in doubt try “yyyy-mm-dd” – this will always work fine"
However, on my iphone,
2009-01-17 imports as Jan 17, 2009 (as expected), but
2009-02-06 imports as Mar 6, 2009 (off by one month)
I'm not aware of any calendar that has March as the second month of the year. Will there be a fix?
Could you please mail your query to firstname.lastname@example.org with your sample csv. This is not the current behavior and we should be able to help you.