Personally, I think we can ignore such a headache as the party member Congress when taking the postgraduate entrance examination. In this case, you can make it clear to the party organization first. You said that you were preparing for the postgraduate entrance examination recently, and I would ask for leave if possible. Generally speaking, the party organization will consider your situation and then give you some suitable prices. I think it doesn't matter much that you don't have to attend some party member congresses as long as it's not very important. It's ok to organize one or two activities once in a while, but after the postgraduate entrance examination period, you, as party member, should not shirk such obligations as a party member.