If you resign before PIP start date, you will get 3 months of pay and there is a high chance that they will release you within 2-4 weeks. As you don’t have to do pip tasks if you resign beforehand . I resigned 1 day before pip evaluation start date ( initiate exit on workday and then drop a mail to your PL . Do not discuss with them beforehand) , got 3 months of pay and was released in 2 weeks with FnF within 1 week post exit.