Pamela, Citizen Contact Centre assigned this issue to Engineering Services

It does seem odd that the advanced turn signals only operate during low traffic hours. Makes it redundant as except for "GP rush hour" left turns are not an issue without advanced green. I turn left at this intersection all weekdays between 4 & 5 PM. Traveling east on 68 on occasion have to wait two cycles before turning left onto Poplar. Rarely have to wait 3 cycles. 80% of time able to turn left at first cycle of green.

Thank you for your comment. The advanced left turn at this intersection is triggered by detection of a vehicle sitting in the left turn lane behind the stop bar. If the light is not being trigger it is a possibility that the first car at the stop bar has crossed the line and isn't being detected.
However with that being said, someone will look further into this issue and adjust accordingly as necessary.

Once the twinning of 68 Ave is complete the lights will be reviewed and the left turn signal will be activated.