It used to be that hitting the refresh arrow/loop button in preferences -> account would pull down a new provisioning profile with all ur new devices.
Now it just do
Spent a lot of time trying to fix the same issue on Xcode 7 i.e. refreshing the Xcode managed provisioning profiles.
After adding the UDID in the member center, what worked for me was just removing the account from preferences -> account and adding it back again. It updated all the provisioning profiles.