Not OP, but this is the same way lightbulb or hard drive manufacturers can claim "greater than 50,000 hours of operation". Instead of testing for over a decade,

Not OP, but this is the same way lightbulb or hard drive manufacturers can claim "greater than 50,000 hours of operation". Instead of testing for over a decade, they test many samples over a shorter time duration, and then they extrapolate. Like any other extrapolation, these estimates have their caveats. But for biological reagents, something like an exponential decay is often considered reasonable.