I doubt sales for phase 2 will wait for phase 1 to occupy. I imagine Phase 2 sales could start as soon as next year, considering phase 1 will most likely be sold out by the holidays.
The first tower is already sold out and I believe sales for the second tower started in late June but I'm not sure if the whole tower has been released for sale.
While personally I'd be happy to see the Phase 2 towers rise sooner rather than later, I think you're incorrect that Phase 2 sales will start soon for a practical reason: Phase 2 requires destruction of the current LCBO offices, therefore it can't start until those offices are moved to the new office at 100 Queens Quay, and those offices aren't due to open until 2021-ish. Therefore I'd imagine sales of Phase 2 can't start until 2021-ish (unless people are willing to purchase pre-construction condos ~7 years before they're built, which is probably unrealistic).