Calm down, people do not live on the board.
CIC gives you a UCI if they send you any communication.
So the sponsor gets a UCI when they send the sponsor approval letter. In my case the sponsor approval attachment filename included my wife's UCI.
While processing stage 2, if CIC need anything from the applicant then they will give the applicant a UCI.
Also if the applicant has applied for any other type of visa/visitor record from CIC then they will use the existing UCI.