iCloud Container name prefix change in Xcode 6

Question

I need to update one of my live apps whose iCloud container name prefix is my TeamIDPrefix. Xcode 6 only allows iCloud container names that start with iCloud.

Problem: If I use the new iCloud container name (with prefix of iCloud), my users would no longer be able to access their data which is in in old container (with the TeamID prefix).

Answer 1

This solved my problem.

1. Create an AppID that includes to iCloud container. It should look like this

2. Make an Entitlement file that looks like this (I'm using only iCloud Documents in this example).

Xcode will show you errors under "capabilities". Ignore the errors and do not hit "Fix it" as it would mess up everything.