1. The court has to listen to the objections raised by opposite advocate in case he informs court about his objections to the petition filed by you, court cannot ignore it, besides the documents may be unnecessary but court will permit the opposite side to file the documents at this stage also because no orders have been passed. The decision will depend on court's discretion and the court will pass order on merits.
2. If the opposite side has filed the petition to receive additional documents, then it becomes your duty to either no objection or no say, hence in that event it will not make any difference whether the opposite advocate is present or absent on that date becasue it is you who has to express say or no objection to his petition.
Whether the documents filed by the opposite party before court bat this stage are relevant or irrelevant will be decided by court on its merits i.e. whether to rely upon them or dismiss the petition.
3. If you express no objection to his petition seeking permission to file additional documents, then the court will post the matters either for fresh hearing of both the sides or proceed with passing orders on the next hearing