Thank you, Sir…
This is a little off from the OP, but I just acquired an iPhone 5s using PA (v4.1.3.14) Method 1, Method 1 + Encrypt Backup and Method 2. I also used other tools, but not talking about them now.
Everything seemed to acquire fine until I loaded the extractions into PA. The only difference between the Method 1 and Method 1 + Encrypt Back up is the "Passwords" section that contains the users credentials.
Method 2 on the other hand retrieved only a fraction of what Method 1 got. It failed to get Calendar, Call Logs, iMessage Chats, MMS, Notes, Web artifacts and a few others. All of these (plus others) were retrieved using Method 1.
I have head of others folks seeing similar results. Anyone know if Cellebrite has acknowledged this as an issue with iOS8?