The parking by-law has passed, FYI. The final by-law went to Council on April 10. If it is not appealed, they won't need variances.
I believe it will be appealed though as IIRC the West End Home Builders Association had issues with the electric vehicle charging provisions, and a few other landowners provided letters to council protesting certian aspects. They will likely appeal as a result, which will mean it will need to go to the OLT before going into force. The main provisions about reduced parking likely wont have any appellants and will probably be "released" by the OLT fairly quickly, but until that happens, it won't be in force, and a variance will be needed.
If Slate isn't intending to go to permit for a little while however, they may just decide to not bother with the variance and wait for the by-law to come into force.