Hi,
As the property is registered in your joint names, your partners name will have to be removed and the property transferred in to your name only and you will have to qualify for the new mortgage in your own name. This means that you will have to reapply for a new mortgage. Are you looking for an increased mortgage to pay your partner off.
I presume you are on a tracker rate and as all the banks no longer offer them you have been offered a variable rate. Please bear in mind that the variable rate has reduced recently and hopefully the ECB will announce a further 0.50% cut this Thursday. This will reduce your repayments. Also your tax relief may reduce as mortgage wil be in your sole name.
Furthermore Ulster Bank would not have the most attractive variable rate on the market at the moment so maybe you should shop around. The best variable rate at the moment is 5%.
Hope this helps
Spin