You’ve identified the heart of the question, T5. There are specific regulations which empower CASA to issue specific ‘things’ – to use a neutral term – with an expiry date. A medical certificate is an example. Part 67 contains provisions about the duration of medical certificates.
When CASA nominated Part 141 Flight Training Certificates as a kind of certificate with a limited duration, I tried to find a provision which expressly empowers CASA to issue those certificates for a limited duration. I can’t find one (and I don’t consider the ‘note’ to be enough because, as you say, it’s merely ‘commentary’ about what could be. What actually happens to specific ‘things’ depends on what the regulations have to say about those specific 'things').
From my perspective, CASA’s inability to provide an answer in nearly a month speaks volumes. I hope to be convinced otherwise and will apologise and stand corrected if I’m wrong, but I’m anticipating some dubious argument based on that ‘curious note’ and the Acts Interpretation Act.
swh. I’m not talking about an “approval”. I’m talking about a certificate.
I don’t understand the distinction you’ve drawn between an “approval” and the “instrument that grants the approval”. In my simple mind, they are one and the same. Please don’t try to explain the distinction, because I doubt my brain’s big enough to understand and, in any event, the fact that CASA might issue something with an expiry date merely begs the question. That is, it merely assumes that which is to be proved: whether CASA has power to do that. That is the very purpose of my question to CASA about Part 141 Flight Training Certificates.
I’ll try to make my point this way: Assuming you are or were the holder of a pilot licence, does it have or did it ever have an expiry date on it? If it does not have and never had an expiry date on it, do you think that’s just a product of CASA being ‘nice’?