DonB_62 Said:
"iCloud Messages > Manage Storage > Disable & Delete: I need to free up 3.2GB of Messages due to my iCloud is full. Seems easy enough just to select Disable & Delete but I read folks have lost all of their Messages on their iPhone after doing so. I so do not want to lose the messages on my phone, only from iCloud. Why are some people saying it also deletes the messages on your phone as well?"
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Downloading All of iCloud:
Seems you know how to all of iCloud, yet are concerned for loss of Messages.
So, what to Perform:
Moving forward, download all of iCloud > Verify that you can access the data, and then trash what is in there. You’d search through the download using the Search Bar located on the top-right corner of the Finder window. In doing so, iCloud will be emptied, backed up, and set up anew. Use my User Tip: iCloud+ Plans and Pricing - Apple Support