Included on the upcoming DVD release of Colony In Space (details HERE) is a Coming Soon trailer for the next Classic Doctor Who DVD, The UNIT Box. This set includes the Jon Pertwee story Invasion of the Dinosaurs and the Tom Baker tale The Android Invasion. January 2012 would look like the probable release date for the set.
ETA: TVShowsOnDVD have announced that both stories will be released in North America on Jan 10 (as separate DVDs), suggesting a January release for the UK too. Details HERE.
Thanks to 2|entertain