Thanks for this info, this makes it a lot clearer. I remember the issues about it being more invasive but don't recall the issues about the frames being in better nick than thought.
Might as well get some coin out of the Canadians for whats left. I can't see the yanks being that impressed. But I don't think they are worried about the Canadians or worried about F-35 sales.
Here's another link regarding 'reprocessing' of information on the structural life of the Classic Hornet fleet:
https://www.dst.defence.gov.au/news/2016/03/24/maths-extending-lives-our-f/18-hornets
I wish I could find the more detailed report I read, but this enough.
One interesting paragraph in the attached article is:
"Over the last 20 years, research undertaken by DST
supported by the RAAF and the broader F/A-18 international users community has built up an in depth knowledge of the critical fatigue damage locations of the F/A-18 and how fatigue damage accumulates in the structure."
Basically what that means, is that the international Classic Hornet user community, including Canada, received and benefitted from the work done by DST and could also apply that information to their respective fleets too. (Going back a number of years, it appeared that most Classic Hornets, not just here but overseas too, would be pretty shagged by the time 2020 arrived).
As it appears likely the Canadian Government will force the RCAF to continue operating their Classic Hornets until at least the mid 2020's (possibly a bit beyond too), you can see how they can get away with that, if they have the knowledge their Classic fleet still has a bit more 'life' left in the airframes that originally believed.
And it makes it even more sense to understand why they would want a number of airframes from the RAAF's Classic fleet, as our airframes are on average 2-3 years younger that the RCAF fleet.
Anyway, still think the Canadian Government should bite the bullet and make a permanent replacement decision, but not holding my breath on that one!!!