One went from indeterminate to positive and one went from indeterminate to negative.
The reason UW asks you to repeat the test in 3 months from the first one is that they are trying to be certain your seroconversion (going from negative to positive) isn’t going very slowly. I would recommend that you follow the directions to do the blot again. If indeterminate,you can be more certain that you are not infected. Just my opinion.