President Assumptive of the High Council
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President Assumptive of the High Council was the title given to Livia after President Romana announced her resignation from the post and named Livia as her successor but before she was formally invested by being given access to the Matrix in a ceremony at the Panopticon. (AUDIO: Enemy Lines) Individuals who were confirmed to the presidency instead by an election were referred to as the "President-elect" before their investiture. (TV: The Invasion of Time)
The President Assumptive had the power to appoint an Acting Castellan, as Livia did with Plutus. (AUDIO: Enemy Lines)