Thanks for the detailed explanation! I appreciate it! I tried googling all the terms, but it was not as clear as how you have described it.

As I currently have no status, if I log into the eUpgrade webpage, it says that I have no credits. (But I am a nominee of my friend and he is Elite) So how would I go about upgrading my reservation? Or will this credit to share status change once the upgrade window opens (T-96hrs)?