Well, as I understand it, ttjtmomma, a WIP is something you have started and been working on right along, but have NOT put it away for any length of time and stopped working on it. A UFO, would be a WIP that turned into a PIG and then got stuck away in the closet or corner under some other stuff... lol... you get the idea, I hope.
I would say, IMHO, that a WIP that was not put away, but has been usurped by at least 2 other WIPs in the actively working on it status, would also count as a UFO.
However, for our purposes, I actually do believe that the definition of UFO is left entirely up to each person, and no one here is going to interrogate you as to it's qualifications for being on your list. We promise to ohhhhhh and ahhhhhh regardless of the age of the project you actually complete each month!!!
Huggggs and smilesssss