FWIW I agree with the above, if it was me I’d just pay it off. @cjr is right about offset mortgages, but realistically if your income is such that you were happily paying the mortgage, you could quickly chunk fairly substantial savings over time anyway, which I expect would also feel pretty fucking good each month once your biggest outgoing (I would imagine) was taken care of.
FWIW I agree with the above, if it was me I’d just pay it off. @cjr is right about offset mortgages, but realistically if your income is such that you were happily paying the mortgage, you could quickly chunk fairly substantial savings over time anyway, which I expect would also feel pretty fucking good each month once your biggest outgoing (I would imagine) was taken care of.