You may recall when Fairmont Public School on Hamilton Road (between Highbury and Gore) shut down a few years ago, the City of London purchased the lands. Not too long after, the Bob Hayward YMCA branch, which is adjacent to the school, also shut down and it appears that the City also purchased that property (though I'm not 100% certain on that).
The city is proposing a new subdivision on these lands with a park and a new road.
I found this from on the ward councillor's Facebook page (Hadleigh McAlister). Note that this is just a concept plan: "the scale of the development will be refined over time based on community and technical needs and input. You can see the current concept design for the site below. Residents will receive future notice informing them of a formal re-zoning application for lands in the coming months"
The current concept plan has two low-rise apartment blocks, two mid-rise apartment blocks, two townhouse blocks, and a park block.