I had to change my I Cloud ID. The change did not propagate to my devices. How do I make that happen.
I had to change my Apple ID. Which also changed my I Could ID. How do I get the new ID on my I Phone and I Pad?
iPad
Go to Settings>iCloud and click 'Delete account' to sign out. (This does not delete the account from the server.) Then sign back in with the new ID. Your iCloud data will disappear from the device when you sign out, but will reappear when you sign back in.