This looks like an upzoning exercise to me. Firstly, we don't have a developer proposing this, we have a landowner doing it. Secondly, the exterior design looks nowhere near complete. To me this looks like Sun Life is just doing the work they need to, to make the property worth a lot more, so they can either sell it as an approved redevelopment site at considerable profit, or—somewhat less likely—would be Sun Life partnering with a developer once they have their rezoning. Either way, I think it's too early to panic in regard to the exterior expression (or specifically the lack thereof).
In regards to the proposed massing, if they were to propose that the tower rise closer to Simcoe, they could leave room for another tower at 217 Adelaide, but they are not doing that. Owing to the narrowness of the 217 Adelaide W lot, the City does not see it as a tall building site. Unless the OMB sees the lot otherwise and allows Humbold to go ahead, Humbold would have to work with Sun Life to shift the 100 Simcoe tower to the east for Humbold to build anything tall on their lot.
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