What is the (auto)save model for macOS applications?

TL;DR --> I use annotations in Preview heavily (many text callouts and line graphics, in multiple colors, etc.) Preview will not properly save these annotations.

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I'm particularly bothered/tormented by Preview.app, but the "model" for "Save" is likely shared by other apps (e.g., the iWork suite).

My configuration: Preview 11.0 (1056.3.2), macOS 14.3.1, M2Pro MacBookPro

This (mis)behavior has been present for a long time (over a year, at least) throughout multiple macOS updates. I have complained both here, in the discussion forums, and in official Apple feedback channels, to no avail. As far as I can tell, Preview.app is a deprecated/unsupported application. It does not appear on Apple's feedback page Product Feedback - Apple. And the feedback I have provided has been ignored: https://feedbackassistant.apple.com/feedback/13510240

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I use annotations in Preview heavily (many text callouts and line graphics, in multiple colors, etc.) Preview will not properly save these annotations. The behavior is weird and incoherent. It seems that only the edits/mods I do until the first "save" are actually saved; all further edits, although shown properly on the screen, are not reliably saved to disk. I am forced to open a duplicate copy of the document, then cut/paste from the original/orphaned document into the duplicate. If I do this "fast enough" (before the first autosave") then the duplicate will retain those pasted modifications. But if I tarry, any pasted edits--occurring after the first autosave of the duplicate file--will, again, be lost. So, I have to work, spoonful at a time, to do any edits, and always examine the "saved" file to confirm that it contains my most recent edits before closing it; because if I close a file that looks perfectly good (onscreen), its "saved" version (on disk) may be missing a lot of annotations; then they are lost and must be redone.

So I've tried holding off on "saving" my work until I'm ready to "commit" them (this is really not a safe workflow; it's better to "save often", but that--as I've observed, above--causes problems.) But this work-around is stymied too, because macOS (or the Preview app) insists on doing autosaves: after the first autosave (whose timing I have no control over, and am not asked to approve), my subsequent edits risk being ignored/lost by a manual (i.e., user initiated) "Save".

I have tried using the "System Preferences>Desk & Dock>Ask to keep changes..." option. Neither selecting nor unselecting this option prevents the app from autosaving. Strangely, when this option is selected, the black dot inside the red stoplight never appears...as though the app is not aware of--or doesn't care whether--the document has been changed(!)

I am asking for further information on Apple's "save to disk" memory model. For quite awhile, their apps have had an inscrutable set of Save-related commands (under the "File" pulldown: Save, Duplicate, Rename, Move To, Revert). Curiously, "Save as..." is no longer one of them. If you explore the "Revert" behavior, it exposes a TimeMachine-like repository. I suspect that this collection of file archiving "wizards" is fubar'ed. Or maybe it just has a complex "model" that I don't understand...hence the title of my question.

But my immediate wish is to "turn off" autosave, especially in Preview, so that I can get back to work on my annotations without having them ignored/lost/unrecoverable. For instance, is there a command line setting to disable autosave?