Plot hole: Jo is surprisingly skeptical about the TARDIS being able to move, considering she saw it dematerialise in the last episode.
The Daemons - S8-E5
Plot hole: It is never explained who - or what - killed the man in the churchyard during the first scene (early in part one). It cannot be Bok (the gargoyle) or Azal (the Daemon) as neither of them have awoken.
Answer: In 'The Five Doctors', three separate Cyberleaders are definitely used. So it's likely that Cyberleaders are like unit commanders, of which a fair-sized army might have several.
Daria Sigma