My understanding is that MTO is making small upgrades to the stretches beforehand - i.e. upgraded guardrails, etc.
I do know the 403 through those stretches was resurfaced last year - I imagine they looped in some minor upgrades with that before increasing the limit.
It's good to see more increases, but I definitely see a lot more room for reasonable stretches to be increased to 110 still:
- 400 Vaughan - Barrie, north of Barrie to MacTier
- 401 Kingston to 416
- 401 London to Kitchener, Cambridge to Milton
- 407 in it's entirety
- 418
- 401 Cobourg to Colborne
- 17 west of Sudbury
- 11 Gravenhurst to Bracebridge
I also think the twinned parts of 11/17 east of Thunder Bay desperately need a limit higher than 90 km/h, be it 100 or 110.