The initial design had platforms on all 4 Kitchener Line tracks but the current design has one island platform between the 2 stopping pattern tracks.

Metrolinx's web page for the bridge: https://www.metrolinx.com/en/projects-and-programs/ontario-line/what-were-building/lower-don-bridge-don-yard-portal

It's likely for the north-end of the 4th Track installation on the Kitchener Line. Track installation seems to be preceded by noise wall installation, which would be a safety hazard, next to the path.

I find in Ontario that there's a "in-practice speed limit" - the speed you can drive without being stopped by the OPP that's higher than the posted limits. This seems to be 120 km/h on a 100-limit 3-lane 400-series and 110 km/h on 2-lane 400-series highways. Not sure what the in-practice limit...

First concrete pour today. I think that’s a tower crane base included.

Noise can be mitigated by locating only the bathroom and kitchen windows on the noise generating side of apartments:

The Trimble device in the pic above is a 3D LiDAR scanner. https://gedo.trimble.com/en Uses include: Final Inspection As-built survey and documentation Quality Control Clearance analysis"

Yes, Wikipedia suggests that the Finch vehicles are configured as cab + intermediate + long + cab and will have a capacity of between 300 and 340, depending on internal configuration. https://en.wikipedia.org/wiki/Alstom_Citadis_Spirit

From this article: https://www.metrolinx.com/en/discover/progress-being-made-to-provide-faster-more-frequent-go-service- "OnCorr includes all works that will unlock faster, more frequent train service, such as track, signaling, electrification work and electric vehicles, as well as the...

http://www.straitsuperport.com/transportation/ This is related to a proposed new "super port"

I suspect we're heading for the following: All Metrolinx locos will be ETCS equipped CN will equip some locos with ETCS so they are permitted to operate on Metrolinx owned track - others have indicated that there are still a small number such service When Metrolinx locos operate over CN or CPKC...

Those aren't unreasonable RfP requirements.

https://urbantoronto.ca/forum/threads/go-transit-electrification-metrolinx.20729/post-1623618 You're likely right that in the high-roof area poles and catenary will be needed but under there isn't room under the historic shed sections.

I believe they're going to adopted "Rigid Overhead Conductor" within the legacy shed. instead of catenary-supported conductor.

I love this quote from the Passenger Movement Modelling Plan: "It is important to note that the Train Service Plan which dictates the train schedule, train placement and passenger demand, is still in a conceptual form and is likely subject to change as the ONxpress design phases advance. It is...