Given that track isn't finished, and zero trains have run through the central section yet - we have zero idea how well the system integration and signalling is working.
It's therefore too soon to say.
Once that "construction" is finished - so much still needs to be installed, commissioned, then tested over and over to make sure it works - and then the collective line needs to be tested with pretend people in it to make sure it's safe to operate. Signalling, radio systems, CCTV, elevators & escalators, lighting, fire doors, fire alarms, fare gates, ventilation & extraction fans, emergency exits, general integration into TTC stuff...
As I said further up this thread - delays at this "final stage" is what caused the 3 year Crossrail delay in London. And how long did RTG in Ottawa test drive trains before the City let them open? Clearly not long enough