OK, I'm coming back with some more clarity on the situation, after doing some testing.
I fired up my Catalina VM in Fusion, and checked for updates.
The Device Support update was there, the Safari 15, and security updates were also there.
Back on the host of 11.6 no updates showing up at this point. I am wondering if it's because I installed iOS 13, and it did it's component update, and that's the same that's included in this update being offered today. That's the only thing I can think of. I checked System information under installations, and I didn't see anything referencing it being installed.
I also looked for a physical installer from apple to grab, but none was found. So, at this point, I am thinking I may not require the update on this particular configuration. At this point, as mentioned above, I don't have any new Apple devices beyond my iPhone 12 Pro Max from last year, so unless I need this to deal with iOS 15 itself in general, then I really don't need it at this time anyway. The other thing I'll mention is, when I connected my iPad Air 2, to the mac to update it to iPadOS 15 on release date, it just worked, so maybe I have what I need already. Who knows, at this point Apple isn't as predictable as they used to be, at least for some things.
I fired up my Catalina VM in Fusion, and checked for updates.
The Device Support update was there, the Safari 15, and security updates were also there.
Back on the host of 11.6 no updates showing up at this point. I am wondering if it's because I installed iOS 13, and it did it's component update, and that's the same that's included in this update being offered today. That's the only thing I can think of. I checked System information under installations, and I didn't see anything referencing it being installed.
I also looked for a physical installer from apple to grab, but none was found. So, at this point, I am thinking I may not require the update on this particular configuration. At this point, as mentioned above, I don't have any new Apple devices beyond my iPhone 12 Pro Max from last year, so unless I need this to deal with iOS 15 itself in general, then I really don't need it at this time anyway. The other thing I'll mention is, when I connected my iPad Air 2, to the mac to update it to iPadOS 15 on release date, it just worked, so maybe I have what I need already. Who knows, at this point Apple isn't as predictable as they used to be, at least for some things.