The official FAQ currently says that after the application and processing fee are received, the process should take weeks, while also making the outcome depend on vetting, timely submissions, eligibility and visa availability. Treat that as general official guidance, not a guaranteed move date, and recheck the current page before payment.
The calendar depends on steps outside the applicant's hands
Three variables make the timing unpredictable. Vetting is conducted by government agencies on their own schedule. The eligibility determination under the underlying employment-based category depends on that category's adjudication practice.
Visa availability depends on the Visa Bulletin, which for some chargeabilities imposes waits measured in years; Canadian-chargeable applicants have generally been current, but the framework does not exempt anyone from the bulletin. On top of these, the program is new and its procedures may be revised. A Lac-Beauport applicant should therefore refuse to make any irreversible household decision on the basis of an expected date: no resignation from a Québec position, no sale of the family home, no withdrawal of children from school until permanent residence is actually granted.
If the household needs to be in the United States earlier, a separate nonimmigrant category with its own eligibility, such as TN or L-1, should be evaluated on its own facts rather than treated as a placeholder. Record the date each official statement was read, and re-read before each payment.