You should do fine. I shot in front of a friend and got my letter. I then took phase 1, for the same reason you are. If you get the 540 during phase 1, you have automatically met the qualification for phase 1 and 2 - PRESSURE IS OFF and your scores go way up.
All of the instructors were told that phase 1 would be the 4 100's out of 7 attempts, so that is what we spread to get officers ready. I did not find out that we were sticking with PPC until a meeting CLEET had with us in February - it was supposed to be January, but snow kept shutting it down.
You might check yourself on the Smith backup course (needed for ALP phase) once in a while also. I don't think it is very hard - just different from the norm, but I have seen some instructors struggle with it.
Don