1989 checks out with GPL v1. The FSF prior to GPL was a bunch of different licenses. The idea is at least that the FSF can update a buttload of code to GPL 4,

1989 checks out with GPL v1. The FSF prior to GPL was a bunch of different licenses. The idea is at least that the FSF can update a buttload of code to GPL 4, 5, 900, etc if a flaw in GPL is discovered.