1.  Absence.  No member of a court-martial may be absent or excused after the court has been assembled for the trial of the accused, except for physical disability or as a result of a challenge or by order of the convening authority for good cause.  

2.  Vacancies.  Whenever a court-martial other than a court-martial composed of a single military judge is reduced below 3 members, the trial may not proceed until the convening authority details sufficient new members to provide at least 3 members. The trial may proceed with the new members present after the recorded evidence previously introduced to the court has been read to the court in the presence of the military judge, the accused and counsel for both sides.  

3.  Military judge.  If the military judge of a court-martial composed of a military judge only is unable to proceed with the trial because of physical disability, as a result of a challenge, or for other good cause, the trial shall proceed, subject to any applicable conditions of section 425, after the detail of a new military judge as if no evidence had previously been introduced, unless a verbatim record of the evidence previously introduced or a stipulation thereof is read in court in the presence of the new military judge, the accused and counsel for both sides.