The TTC scheduled 3 runs for each of the morning and afternoon rush hours, signing eastbound streetcars as "504 Parliament" and westbound as "507 Long Branch".

By February 1994, the experiment was deemed a success and additional afternoon rush-hour trips were added.

[6][7] On March 24, 2020, the 508 Lake Shore route was discontinued due to low ridership during the COVID-19 pandemic.

[9] With the completion of infrastructure work west of Roncesvalles Avenue, the TTC scheduled 508 Lake Shore to resume between Long Branch Loop and Parliament Street effective October 30, 2023.

[10] On weekdays (excluding holidays), 508 streetcars ran every 20 minutes in peak periods, leaving Long Branch Loop eastbound in the morning rush hours, and leaving Parliament Street westbound in the evening rush hours.