Right that makes sense, if you'll be settling a large chunk of the balance then the ERC is relevant. However, is your ERC constant throughout the term of the deal? I'm with Halifax and I believe (although not sure now if I'm wrong!) but I think ours reduces by 1% each year, so is 5% in the first year, 4% in the second year and so on.
I can totally see the rate dropping quite considerably before the end of the year because of the upcoming election - never know what might happen but I'd be very surprised if the rate isn't a lot lower than it currently is by the time of the election (and the same will most likely happen in the US too).