The "detailed guidelines" can be found here:
https://www.ontario.ca/page/reopenin...after-covid-19
There are no specific numbers of cases mentioned. One of the key milestones for Stage 1 is
"a consistent two-to-four week decrease in the number of new daily COVID‑19 cases." I do think the specific numbers will influence just how quickly they reduce restrictions, but I believe that certain outdoor activities like golf will be one of the first areas where restrictions are loosened.
The fact that testing is more widespread now than in the past is not really relevant - the document is a guideline for the future that assumes the current level of testing or more.