Confirmation will be sent by emails to potential sponsors of parents and grandparents. As of 19 March 2018, potential sponsors can confirm whether or not they have been selected by looking up their unique confirmation number to compare it with the list of numbers that were randomly selected:
Note, that if Immigration, Refugee and Citizenship Canada does not receive 10,000 complete applications, additional potential sponsors will be invited to apply later in the year. So, if you have submitted an interest to sponsor form in 2018, keep monitoring your email.