Great photo!
I'm going to post it on the Canada site.
As for the construction schedule, I imagine it has to be choreographed to make proper use of the crane. Since the crane is currently located in the centre of the building (ice surface area), it makes sense to continue working on the north side of the building before proceeding to the south side. The crane will likely be located on the exterior of the building when the south side is completed (we don't want the crane to get trapped inside the arena do we?).
Finally, you can see where they're working on the parking lot next to Heritage Court as well. This lot will be used for event parking for the Events Centre in the evening and will be connected to the centre via a tunnel under the CN main line.