Welcome to the Continuity Cops mailing list. This list was created to allow a forum for discussions of continuity issues relating to the massive expansion of the DOctor Who 'universe'.
For the purposes of this group, everything that was licensed by the BBC is 'canon' - TV stories, novels, cigarette cards, Weetabix boxes, annuals. This isn't a definitive statement on the canon debate, just a way of making the discussion as wide as possible.
... Nah. It means that Dimensions in Time, Search Out Science, etc. happens before Ace's mind-wipes in Loving the Alien and Timewyrm: Genesis... Stephen
The Seventh Doctor appears with both K9 Mark I and Mark II in "Lungbarrow", but they are on Gallifrey, not traveling with him. This is also clearly Ace's first