Marcus Wilson, producer, has said in Doctor Who Magazine that two monsters from the ‘classic’ series will pop up at some point in the season, though whether this be in a “Dalek-in-The-Wedding-of-River-Song” sense or a “Ice-Warriors-in-uhm-The-Ice-Warriors” way will obviously be left unconfirmed for a while yet.
SFX, meanwhile, have speculated over the transmission of the series:
“If the series is still shooting in December it seems impossible that it will be transmitted in one chunk – a gap in transmission seems highly likely. But how big will that gap be? Will there be fewer episodes transmitted this calendar year than any other when the show’s been on air? (That looks likely.)”
Showrunner, Steven Moffat, previously stated that Doctor Who will be “back in the Autumn for a long run. I will just say; it will be at least 14 episodes. We always do 14, because we do the Christmas special as well.”