Toronto Fire Aerial Firetruck's Ladder Going Up

One of the city's 30meter ladder trucks out front of Station 114 at 12 Canterbury Place North York doing some test/maintenance review of some sort.
My kids and I came across them while playing in the park behind the station and rushed around to see what they were doing (they were testing lights before this).
Note: While this is Station 114 which is usually home to one of the city's 3 Tower Trucks, as opposed to the Aerial Truck, there is no articulation in this ladder so it is an aerial (must be on loan to the station).

[@fd-pr5dl]

It's a spare truck.
When Tower 114 is in for service/maintenance/testing, it is removed from service and a spare truck is used instead.