It may be the language you’re using to try to explain the structure that is causing the confusion. Or perhaps I’m confusing you (or myself). I apologise if I’m confusing you.
This confuses me:
The only change was a change of name of the parent company from MFT to APTA. The trading name MFT remain unchanged.
Why did you use the term “parent company” and, on your understanding, of what other company/ies was that company the “parent”?
On the ‘pure’ APTA ‘alliance member’ model, no member needed to be a related entity - parent or otherwise - to any of the others or APTA in a corporate law sense. That’s why I’m confused. (In any event and importantly, even if any of them was related to the other in the corporate law sense, they remained separate legal entities. That’s what gave CASA the vapours and resulted in the ultimate demand for evidence of effective control over non-employees etc.) It may be that you’re using the word “parent” as your layperson’s description of APTA’s ‘position’ in the ‘alliance’ ‘hierarchy’? That’s fine, so long as there’s clarity of what you mean.
In relation to the ‘parent’ company, are you saying that it started out being named MFT and then its name was changed to APTA trading as MFT, but with the same ACN throughout?
CASA’s letter of 23 October 2018 clearly treats the APTA entity to which CASA wrote as being a separate legal person to e.g. the MFT entity mentioned in the letter. Either they were one and the same entity or they weren’t. It would be unusual even for CASA to make such a big stuff up, but I suppose almost anything is possible.
One of the published attractions of the APTA concept was that each ‘alliance’ ‘member’ - not APTA - would retain “complete control” of its “business” (and I’ve noted before why those words evidently caused APTA so many problems from CASA’s perspective). On 23 October 2018, who was in “complete control” of the “business” at the MFT ‘base’ in the sense APTA used the word “business” on its website?
When you opened “your” flying school, was the AOC authorising that operation issued to a natural person or a corporate entity? If it was issued to a corporate entity, can you remember whether the ACN of that entity was the same as the APTA entity on 23 October 2018?
I understand all this corporate stuff can be complicated and confusing, but if you’re not across the detail it’s going to be difficult for you to explain it to e.g. the Ombudsman. After all, it was your trainset. (I occasionally fear that you might’ve been the victim of a corporate pea and thimble trick yourself.)