"I would imagine that your penalties and charges will far outweigh any savings you will make over the next 8 months from your new mortgage."
I would agree with this. Currently I'm on 6.4% and looking at a 3.4% mortgage which will save me over £300 per month. However the early redemption fee is more than I would save over the 2 year fixed deal I would be going for.
However apparently I can book this deal now to start in July when my current mortgage ends and therefore secure the 3.4%. Rates are only likely to go up over the next few months..