I hope I am wrong too. Retconning a show usually backfires. Like many associated with the old series have noted-no matter what they get rid of, be it monster, character, or obscure bit of Wholore,it will be SOMEONE"S favorite. So any change will end up bothering some diehard Doctor Who fans. Generally not a good thing to do when attempting to get a series up and running.
But, rewritting seems to be the rage with revived series, and the timewar will allow for any sort of change (like the rumoured new Dalek design). In theory it could be a good thing, allowing the writers to update some of the classic monsters so they can pass muster in the modern era, so they look less like guys in rubber suits.
It also allows them to reverse anything that doesn"t work. For instane if the new spider/hover daleks don"t catch on, they can be "timewared" right out of existence. Maybe even a story where the old and new daleks fight amongst each other to determine which are the "true daleks".
Heck, this might even be the backstory for the new dalek episode. Or not. Time will tell.