rbcma85, changing the Apple ID shouldn't because you're not erasing the iPhone. But I wouldn't rely on anything with 100% certainty with Apple, lol.
I took the iOS 9.3 updated a few days ago and 1000 iTunes songs, 10 videos, and two ringtones, disappeared from the iPhone. Fortunately I back things up and restored them. Only to have them disappear again the next day. Brought them back again and they have now stayed.