All depends on how badly you have to damage the roots in the process. If the plant is root bound but the medium is still in fairly good shape, I would wait.
If the medium is that bad, then repot. The plant's health is more important than a seed pod. But I do think that repotting shouldn't bother the pod too much, I've repotted blooming phals before and they've always come through fine. The biggest risk is more likely to be accidently snapping the pod off as you manipulate the plant.
__________________ Camille
Completely orchid obsessed and loving every minute of it....
Yukonphal - I agree that you need to repot now for the sake of the plant. I would try to disturb the root ball as little as possible. If the medium is that bad, you should beable to most of it out by spraying the rootbal with a garden hose.
When you repot gently work the new medium into the root ball, tapping on the side of the pot or tapping the pot on the table will help to settle and work in the medium.