It’s brought down in Halacha that if one makes a siyum during the 9 days they may eat meat. A person happens to have a siyum coming out now in the 9 days (he is only one daf away.) However not every siyum he eats meat. Some siyumim he makes by himself without a “celebration” and an official seudah, while other siyumim he makes on Shabbos (specially for the reason that he is anyway eating meat then and having a seudah that it would be nice to use to celebrate the siyum instead of doing it special during the week when he may not make such a big seudah with meat.) In short this person sometimes does make a seudah with meat for his siyum and sometimes not. May he make the siyum now during the 9 days and serve a meat seudah to his family?
There are those who are stringent for one who never eats meat and a seudah for a siyum. As long as one sometimes does have a seuda with meat, he may certainly do so during the 9 days.