How do i change the icloud account on my iphone to a different existing account

Question

I have a business iPhone 5S on which the iTunes account is associated with the Apple ID I signed up for using my business e-mail. I signed in to iCloud with a personal Apple ID account to get some of my personal music onto the device. I have been trying to find out how to change the iCloud account to my business Apple ID. I'd like to be able to switch back and forth if I want. I have read several posts that advise deleting the iCloud account, but I still have personal devices I would like to continue to use with this Apple ID and iCloud account. The extent of the deletion is not addressed.
If I use the delete account under iCloud, does that delete it from the device, or does it delete it permanently? Tried adding my business email to the iCloud account, but it won't let me because it is associated with another Apple ID (duh). Am I stuck here?
iPhone 5S, iOS 8.1 - just updated.
The only option under iCloud is "Sign Out"

Answer 1

Deleting an iCloud account only deletes it from the Device, not from iCloud.  In iOS 8, the name of this setting changed to "Sign Out" as that is a better reflection of what actually happens.  Your iCloud data remains on the server, available to devices still signed into the account, but the device you sign out of the account on is disconnected from the account, and as a result, the iCloud data from that account is removed from the device.  It will redownload to the device should you sign back into the account.
The only issue you'll run into when you switch between accounts is with my photo stream photos older than 30 days.  When you delete (or sign out of) and account, your photo stream photos are deleted along with the other data from the account in question.  However, unlike other data which remains on the server and can redownload to your device when you sign back in, my photo stream photos only remain in iCloud for 30 days.  When you sign back in, you will only get back my photo stream photos added in the last 30 days (as older photos are no longer in iCloud to redownload).  Like other account data, any my photo stream photos on your other devices signed into the account are unaffected by this.  If you want to keep older my photo stream photos on your device as you change iCloud accounts, save them to your camera roll before deleting (signing out of) the account.