Per ASA, again, contact is not necessary for there to be obstruction. If the ball was not on the way to the catcher and the catch not immanent, she should not have been in the base path. The runner should not even have to step around her, if she does have to step around, it is obstruction.
If the umpire signals for an obstruction, the runner can not be put out between the base she left, and the base she is going to. Even if the umpire feels she would not have made it anyway, by rule she is returned to the base she came from.
This is what hte head umpire from our area says.....no need to job around the catcher...without a ball she is obstruction