Instead of minimum no. of lots if a retail investor applies in maximum permissible no.of lots in a single application. Will there be any advantage in case of a oversubscribed IPO?

The retail quota is the number of shares that are available. This divides by the minimum lot size. If 10 lakh shares are made available to retail investors, and 2000 shares is the minimum lot size, then 500 applicants will be eligible for shares. A lottery is used to select applicants if the number of applicants exceeds 500. It doesn't really matter if you apply for minimum or maximum lots.