Going part interest only/part repayment is probably a good* tactic to tide yourself over a hike in payments.

However, the size of mortgage you have makes it worth considering a 2 or 3** year deal so that you are not accidentally on the interest only bit for too long.

In your shoes, i would certainly consider the option of taking a deal that tied in with the 'kids out of the way' moment - that will be a very good moment to completely reassess the mortgage to suit your new circumstances.

Statistically as well, it is very risky planning to overpay - I saw figures that stated that about 2% of people who plan to overpay actually do - I would avoid joining in with that statistic if I were you.

Hope that helps

Adrian

*Good - meaning 'least bad' - no point having an unaffordable mortgage, so while interest only is generally a bad thing, it's better than struggling.

** not necessarily lower rates - but possibly most suitable. The 5 year fixed rate is lower becuase HSBC predict rates to fall - they are in it for profit, and the get out clauses are steep.