boxe-x,
Thanks for the notes. Luckily I have a resonably open wallet but not so open I can afford an a/c on my own. The CofA in this case is around 700!! It may be worth moving it to the Nreg just because of that... and out of spite! (It's always good to rant about the CAA but on a cool head I do think that it's not fair to change every taxpayer for the hobby of a few as it happens in the US).
Happy to hear about the corrosion issue. That was frightening me quite a lot.