General relativity makes certain predictions, we now measured a deviation from those predictions assuming a specific model of the source of the observation. So more measurements will help to build up confidence that the deviations are not just measurement errors.
After that you have to explain those deviations and the two most obvious options are that either the model of the event or the theory itself is wrong or at least not accurate enough to describe the observations. Then you can look for changes to the model, varying masses or the number of objects involved, or maybe even look at entirely different possible source of gravitational waves to explain the observations.
But if you return with empty hands you will have to take the option serious that a modification of the theory is required. For example if you theory only allows a quantity to decrease monotonically over time but your observations show oscillations, then you have pretty strong evidence that your theory requires modifications.
After that you have to explain those deviations and the two most obvious options are that either the model of the event or the theory itself is wrong or at least not accurate enough to describe the observations. Then you can look for changes to the model, varying masses or the number of objects involved, or maybe even look at entirely different possible source of gravitational waves to explain the observations.
But if you return with empty hands you will have to take the option serious that a modification of the theory is required. For example if you theory only allows a quantity to decrease monotonically over time but your observations show oscillations, then you have pretty strong evidence that your theory requires modifications.