From WikiHow:

• During the waxing gibbous moon phase, the moon’s illumination is increasing with more than half of its surface being lit up. This is the phase before a full moon.
• The waxing gibbous moon signifies the final stretch of completing a project. It is the phase for knocking off tasks and tying up loose ends.

Maybe this is a good metaphor for retirement. Try to go out on a high note—building to your full power. Maybe retirement should be the time when you become the best, fullest, most authentic version of yourself.