Yes, I understand. However, it sounds suspicious that we’re suppose to be using some rows with final_rinse for training but not for prediction (the test_values do not have a single row with final_rinse).
Good questions—this is by design. We want to be able to predict the turbidity before the start of the final rinse phase (so it can be adjusted if needed). This means you are not provided any final rinse data for the test set. However, the turbidity that matters (which we want to predict) is only during the times marked target_time_period, which is not all of the final rinse.
For the training set, you are provided all of the observations, which you can split with whatever strategy works best.