Just out of curiosity, was reading through old forums and came across this thread:
I've established iMessage on a new device, did not restore from a backup, and many months of old iMessages were downloaded when I began a new conversation with a person with whom I'd had a past thread.
I was able to pull iMessages from old deleted message threads on a new device.
Is still something that occurs through Apple? Seems like a security issue if you can setup a new device with your iCloud and all your deleted old message history populates? Can you restore deleted iMessage history to a new device, or the same device set as new?
Has anyone tested this?