Nope, you are not doing something wrong. I realized that I had not fully understood the system, and decided to remove doing a 3rd and 4th career phase until I resolve it.
From what I've gathered, you can do up to 4 phases, but as soon as you pick an Iconic Career, you cannot do another phase (i.e. the iconic must be your last career phase). I had not implemented it that way.
You can only do one Iconic Career phase (one phase, one career - you can't repeat your existing Iconic career either), it doesn't end character creation, so you can go back to primary careers afterwards if you wish.
Game Development - 2D20 System
System Design - Star Trek Adventures