Any objection to a planning application being made by a PC, really ought to be supported by valid planning reasons. An objection on its own will carry very little weight with the planning officer. If a NDP is in place, it would be logical for the council to point to the precise policy in the NDP that supports their objection.
In the same manner, the applicant for the planning consent could write to the planning department with reasons why and how, the application is supported and complies with the NDP policies.
It would be also worth waiting to a few days before the deadline for comments, and write a rebuttal to any objections that have been put forward up to that point. Again backed up with policies reasons from the LP and NDP. (If more objections appear on the website after the closing date - write again - the officers will usually include that response as well).