Email sent out by the NPGMC:

"High NPGMC

October brings the long-awaited download of the controversial new album from Prince, The Rainbow Children. On October 17th, Premium Members of the NPG Music Club will b able 2 download a preview release of the entire new album."

(note that they are calling it a "preview release"...kinda gives the indication that TRC will be released again at a later date...)