Generally speaking, the corresponding date after "the objection review is pending" is the pending review date, that is, the time when the trademark is challenged for review. "Objection review pending" means that a trademark was re-examined on a certain day in a certain year, but the re-examination case has not been concluded and is awaiting trial.
The corresponding date after "objection review is completed" is "completion date". That is, the review case has been heard, and the review ruling has been delivered to the parties or their agencies on a certain day in a certain year.