I’d like to know what is significant when it comes to long term...

I’d like to know what is significant when it comes to long term pumping.
How many days after steady state?
The studies by AMN are just as arbitrary as those used by RWD assuming steady state was reached by both.
Again another concept.
What appears to be clear from researching hydrology is that pumping tests are always planned before execution.
Why did the AMN test durations vary so much? Was it a variation in time to achieve SS or a result of arbitrary decisions? Steady state plus a fixed duration? Was that duration statistically significant?