That is the one benefit of the OBRY’s conversion. It will connect to two other existing rail trails, allowing you to get from Brampton or Tottenham to Elora almost entirely off-road by bike (there’s a short on-street detour in Fergus). Theoretically, you’d be able to go all the way to Owen Sound, but the Dufferin County portion of the old railway is in poor condition.
What’s needed next is a better connection between Elora and Guelph and completion of the Guelph to Goderich trail, which has several gaps where CP removed bridges, and improvements to the old Owen Sound line between Orangeville and Dundalk.
From Tottenham, there isn’t a clear bike-friendly way to go to Barrie, though part of the old Beeton Sub is in good condition near Cooksville and Thornton.