Erev Shabbat Parshat Nitzavim-Vayelekh - Short Thoughts

As in Ki Tavo, Parashat Nitzavim contains a brit of sorts as well as a tochecha (rebuke) of sorts. Commentators point out that there is a significant difference in that Nitzavim has an abrupt shift from the previous parshiyyot -from  second person plural to second person singular. What does this mean? One may be highlighting the role of the individual - but which parsha does this?