What we knew from last year:
1/ Online form: very simple, only name, address, email. This year is much more involved such as tick box confirmation for: your own parents, minimum income, etc...
2/ IRCC sent our regret/invitation emails on April 26, so nearly 3-month windows after closing the online form, and this was round 1
3/ Then on September 6, there was round 2 for extra invitations since IRCC did not receive 10,000 completed applications. However, in round 2, only the person who was selected were contacted. Also, the confirmation numbers (of those who were invited) were available to look up as a list on the website. So round 2 is 5 months apart from round 1. The 5-month window must have included the 3-month completion time-frame and 2 months to handle the codes and all... of course my presumption.
So again, my guess would be April for the results of round 1 and September for round 2...