The Court of Appeal sitting in Abuja will on September 14, hear the appeal filed by the Bayelsa State Governor, Douye Diri.
He is challenging the judgement of the State Governorship Election Tribunal, which nullified his election.
On Thursday, some factional members of the Advanced Nigeria Democratic Party (ANDP) brought an application to be joined as parties in the appeal.
ANDP counsel, Kehinde Ogunwumiju, said a notice of preliminary objection which is challenging the competence of the application has been filed.
Justice Stephen Adah said all parties will be allowed to respond to the application filed by the ANDP at the adjourned date.