I am aware that I can configure Lightroom Desktop to save my originals to disk. However, as far as I see, I cannot sync any information on the edits that were made along with them. How would I go about migrating back from Lightroom CC to Lightroom Classic along with my edits? Or Is that not possible at all?
I'm not clear about what you want to do with the locally stored copy of the originals. That option is basically to allow the user to be able to work when the local system is offline (e.g. travelling with a laptop into remote areas), and just like Classic they are original files only and all the associated edits are retained in the local and cloud catalogs. The only difference between Classic and LrDesktop is that Classic does have the option to save metadata to XMP, thus storing the edits in the file header or XMP sidecar (depending on image format), but even then that edit data is generally only useable by another Adobe app. What is it you wanted to use that local copy for?
In terms of migrating back to Classic, there are a couple of methods, both with some drawbacks. Assuming all the images in the cloud are originals, not smart previews synced from Classic, you could either:
1. Simplest method is to create a new empty catalog in Classic, then open the Classic Preferences>Lightroom Sync tab and there set the download location where you want the downloaded images to be stored. Also set the folder structure from one of the standard Lightroom date-based options. Once that's done, enable cloud syncing.....that will then download ALL the images in the cloud to the local hard drive as per the set location, storing them in the capture date-based structure that you selected. It's as simple as that, and once downloaded (and checked and then images and catalog backed up) you can delete the contents of the cloud (optionally resyncing smart previews from the new Classic catalog back to the cloud). Whilst all edits are retained, and most other metadata (albums in Lightroom will appear as collections in Classic, but the Folders do not sync so you'd need to manually recreate the Collections Sets in Classic), the main drawback with this method is that any Keywords, Location Data, People data that you may have added in Lightroom is NOT downloaded and so would be lost and the work would have to be redone in Classic.
2. If the missing Keywords, Location Data is a show-stopper, the other way of migrating back would by by exporting all the images from the cloud using the "Original" option, then importing the exported files into a new Classic catalog. That would at least retain all the missing data from the sync download method, but it also has the drawback that the XMP data in the exported originals does not include Collection/Album membership....so you would lose all that work. The workaround for that would be to add album-specific keywords in Lightroom before doing the export, which would allow you to at least rebuild the collections in Classic from the keywords that you added. You'd also need to think about physical folder storage options....if you exported all in one go from Lightroom they's all end up in a single folder. That's OK, as when you subsequently do the Classic import you could use the "Move" option and choose one of the date-based folder schemes in the Destination panel.
Thank you for that very in-depth answer, Jim. I'm mostly looking to have a way out for my large collection of family photos and their metadata. Say Adobe kicks the bucket sometime (not that it would look like it stranger things have happened), I will be in a situation where I cannot afford monthly payments (also not likely but who knows) or simply a better competitor arises, I'd like to know if I will lose my work or not. I'm aware that adobe is not in a position to provide a means to keep my edits - that's adobe tech after all, and I'm okay with exporting/downloading my work if necessary. However, losing Metadata like albums, keywords, people etc would hurt - a lot. So if that's a no go, I'd rather look elsewhere. The beauty of the xmp files was that they allowed to parse the information, so all the data was available to you in principle. I'm not sure whether that's the same for the LR Catalog, but I will check.
Additionally, I saw that Adobe offers an API to their cloud services, so using the api might also be a way to extractt he information via a script, but again, I'll have to double check.
Thanks again for taking the time to type all this out, that was really helpful. Do you happen to know whether metadata is also stored in the dng files? I seemed to remember that being the case, but I may very well be wrong.
If you're looking for an exit strategy (from the cloud or from LrClassic), exporting all images would be the option that preserves most of the metadata that you have added. You can export as "original + settings" or as a derivative such as Tiff or Jpeg (or perhaps both, i.e. keep the original raw files with settings, and also have an RGB file such as Tiff or Jpeg with all the edits baked-in). The only thing that gets lost using that method would be the album/collection membership, as that's not included in XMP....however, you can get around that as I mentioned earlier by adding an album or collection-specific keyword to the images prior to the export.
The cloud has another exit option, called the Adobe Lightroom Downloader, which can be used up to a year after the subscription ends (i.e. to allow the executor of a deceased subscriber time to download all the cloud-based images if required). It basically downloads all assets into a local date-based folder structure. However, I don't think the Downloader is yet in a good-enough development state to be used effectively, so exporting would be my recommended method.