Earlier this week, the party's executive recommended that the vote be set for May 25 of next year.
The date needs to be ratified by a vote of the provincial council, which now says a decision won't be made until the issue has been discussed at a meeting on Nov.17.
The council says the meeting, immediately following the party's convention, will allow for a better process for discussion.
No candidates have officially declared they'll join the leadership race to replace Dix since he announced his resignation last month, but NDP finance critic Mike Farnworth and MP Nathan Cullen have expressed an interest in the job.
The New Democrats lost to the Liberals in May's provincial election despite entering the campaign with a 20-point lead in the polls.
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