I've complained vociferously about the 506 - but to be honest, I've found it's running near clockwork since the detour on Dundas ended in December. I've just taken it today, and it was near perfect and regular.
Getting across to Exhibition has always been a pain. But I get there a lot faster from Gerrard and Woodbine. But I take the GO Train from Danforth.
I'm confused though why it showed you 77 minutes - which would be 12:22. There's an 11:45 GO Train from Union that arrives at 11:52 at Exhibition. and it doesn't take 40 minutes to get to Union - (and good backup with 506, 505, and the 121). Heck, your only a 25-minute walk to College station.
Sometimes you have to coax these apps a bit to get the GO Train.
I just got back from a trip to John and Queen (and there's no way I'm driving and parking that one). It was 38 minutes from a stop near Woodbine and Gerrard on the 506 and the University subway to Osgoode station. Then I made several stops on the way to the St. Lawrence Market. And finally home from the market again in 38 minutes from the 121 stop at the market to the 506 stop near my house (about 13 minutes to Gerrard and River where I change to the 506).
The Ontario Line will certainly help with trips for me to Queen West, Chinatown, and Exhibition, with the new subway station at Gerrard and Carlaw!
The one disadvantage of driving downton, is I tend to stop here and there for various sundries - which becomes nigh impossible while driving.
2043? I was pleased today to see all the construction underway at Parliament and Front for the new Corktown subway station (it's the launch location for the TBMs to Exhibition). The new subway station at Exhibition is combined with the existing GO station at the bottom of Atlantic Avenue, just north of the Gardiner - so not far from Enercare.
Metrolinx has improved on their contracting for this type of stuff. I don't think they'll be massively behind their 2031 deadline (which isn't finalized yet, as they still have a couple of major contracts to award). You should be in your early 60s at best. With a lot of luck, you'll be 59! Though you seem to be at exactly the wrong spot - being about a 20-minute walk to Gerrard, Riverside, Corktown stations, and Moss Park stations.
Here's a render of the future GO/Ontario Line station at Exhibition. The two tracks for the Ontario Line are on the left. You can see the Enercare Centre in the background.
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