There is no date yet for when the O-Train will offer more frequent service.
A $59 million upgrade includes a double track and trains every eight minutes, instead of the current fifteen.
Councillor Diane Deans, the chair of the transit commission, said on Wednesday she has been asking the city's deputy city manager who is overseeing the project when it will be ready.
"Well, hope is one thing. I mean, I hope to have it up and running as soon as possible but there's a number of Transport Canada regulations and a number of hurdles that we have to cross and we're not there yet."
The extra service is supposed to help move people when the Transitway shuts down for LRT construction later this year.
She ruled out a major shutdown, like the 18-week one last summer.
Transit manager John Manconi added there will be "minor interruptions" due to required testing of the system, but those dates are not yet known.
"And I just want to remind everybody that's it a live system, it's not a greenfield development. You've got an active system, we do night time work and then you have to do the testing and commissioning on off hours."
Currently, service is already ending at 10 P.M, which is earlier than normal. Replacement bus service is being offered after that.