As I've said, the pressure test is just a snapshot in time, so it only tells you the current state of the seals. It's not a predictor of the future state, so how do you know how long the seals will last? I guess my view on this is that factory recommended service intervals are for the entire watch, not just the movement. All watch companies replace all seals every time they service a watch, and that service interval is generally every 5 years or so (yes some are more and some less, but this is sort of the typical length I've seen over the past couple of decades).
If you take that as a guide, then the seals should last 5 years or so. I think replacing them every year is overkill myself, but it depends on how much the watch gets used and how it gets used. With the crown seal on the Speedmaster Pro being "worn" every day during winding, it is likely the weak spot. If you don't wear the watch every day, and like most here have a rotation, then I would be more inclined to let the seal change go a little longer than someone who winds and wears it every day.
But in the end, you have to do what you are comfortable with.
Cheers, Al