Mr Abdullahi maintained that the Tinubu administration had failed a key test of governance.
He said Messrs Abubakar and Amaechi represent a truly national team that bridges regions, generations and political traditions.
The group noted that ADC was attracting growing national attention.
He said the date reflects the belief that citizens’ voices matter.
Mr Abdullahi said the Supreme Court had affirmed the legitimacy of the party’s leadership.
The primary election is scheduled for May 25.
He stated that the action by the ICPC suggested panic, fear, and an attempt to intimidate ADC leaders.
African Democratic Congress has welcomed the ruling of the Federal High Court, Abuja Division, on the deadline for party primaries, among others.
The group said the march is not a conventional party rally but a coordinated civic action for better governance.
The party regretted any inconvenience the adjustment might cause.
