It's been a while since you were involved with the interview, FOMere2eternity? The years and months question doesn't feature, nor has it for some time. Much of the process hasn't changed in 20+ years, but the interview has and is set for further changes in the not too distant future.
The rest of the advice you offer nickyg is generally sound, but I would add:
If you spent 6 months after your A-levels lolling around doing very little, they'll exploit that and dig into the subject.
No more so than digging in to what level you were involved in the organisation of the hockey team you claimed to play for when you were 12-16 years old etc. The gap periods are no more interesting than any other part of your life unless they are exceptionately long (a couple of years) or numerous. Be prepared to say what you were involved in at any stage of your life from age 11 until now, but don't worry just because you had 6 months out of work, going for interviews and having nothing to show for it at the end of things.
...I suggest you go in-depth with about 5 main subjects...
A good general guide would be a international story from each continent and a home affairs story for each of the pillars of government (Transport, Health, Education etc). You are trying to prove that you are interested in wider affairs, not just stories that directly affect your interests.
...just make sure they're not too radical ie. we should never have gone to war!
If that's your opinion and you have reasons why you hold that view, then be honest! Originality of thought and ability to reason are aspects that you want to be strong in, so hold true to you own opinions and expect to defend them whilst taking in to account or countering arguments that the board will raise. You cannot fail for have a 'wrong' opinion, the only questions that you can get wrong (apart from facts about your own life history) are the drugs, previous offences and attitude to warfare questions.
Other minor tips: don't bull**** because they'll spot it and help you dig...
and dig and dig and...
Finally, enjoy it - this is the last tme you'll ever have a chance to play the computer aptitude games which you already know you can beat. You've worked hard at school/college; you're at uni; you're in the UAS; you know what you want to do in life - all of this puts you in the top n% of age group. You have much to offer the RAF, so don't stress unecessarily, just continue to prep.
See you soon.