Nah i'm pretty sure Revelations started off as RE Portable but they switched platforms because of the 3DS tech.
Take this with a huge grain of salt but on a board I was on years ago had a member who was familiar with the situation and claimed as such. Combine that claim with the fact that Slant Six was a fairly prominent PSP dev and you see why I hold that belief. We'll probably never know for sure but RE PSP=Revelations is a misconception I enjoy trying to clear up.
All the cancelled PSP games over the years, including the one that started this thread, are quite interesting to me as someone who loves Sony handhelds and wishes their full potential was met.