You, and everyone else. Later FP+ slots for headliners will be the difficult ones to get. I'd expect most of them to be booked at 60 days out once the system is in full swing.
But that's the rub.
This will be the new norm for us hardcore people (which I consider DIS users to be, the 1% of parkgoers who plan and know all the ins and outs)
I don't think it will be "everyone else" at least not for a while, but it WILL be all the DISers.