12 months to go - should I fix or stick with variable?

Poulaphuca

My current deal with the Halifax has come to an end, so I've taken a month off my fixed deal and put a load of savings into repaying my mortgage.  I now have a balance of £75k, with a theoretical remaining term of 9y 6m.  About this time next year, I will receive a lump sum that will enable me to pay off that balance and become mortgage free.  My question is what should I do between now and then?  Do I stick with the Halifax at their variable rate of 7.99% or sign up for their minimum term of two years and pull myself out of that deal in 12 months time with the lump sum that will arrive then and pay the exit charge, which will be 2% of the balance. 

So £75k * 7.99% for 12 months = £80,992
or
£75k * 4.7% for 12 months = £78,525, plus a 2% redemption charge on the balance at that point (balance likely to be about £33k) = £600.  Thereby giving a total cost of £79,125. 

This makes it seem like I'm better off to sign the 2 year deal but I think I must be missing something.  What's the best path to achieving this magical mortgage free status by this time next year?