Your first link to OPG - suggests, when looking at https://www.opg.com/about-us/ - that they have TWO nuclear power stations in their fold, and it's not clear how many of them were refurbished over what time period.
Your second link suggests a refurbishment of ONE power station.
Okay, so not to detract too much from this tiny handful of refurbs - where the assessment, design, build etc were already done, and target state was well understood (it was to get back to whatever parameters and specs they had previously built at the same location), are there any contra-examples of Canadian hubris around budget and schedule on large projects where things might go wrong?
Eglington Crossing light rail - 6 year delay (to 15 year total) with a tripling in cost to $15B - so about $1b per kilometre of light rail.
Peace River hydroelectric - costing double ($16B) original budget.
Vancouver wastewater - a 4x budget creep (to $4B) and a 10y delay so far - it hasn't opened yet.
My point is that it's not only nuclear fission power plants that are grossly underestimated in terms of cost and complexity, but rather, all large infrastructure projects.
Just happens that on top of all that, the estimated numbers for LCoE, payback, clean-up, opex, etc for nuclear fission are also misrepresented (or misunderstood, depending how cynical you are).
Since 1999?