don't worry so much about your planning exercise, make sure you can do your mental arithmetic and think logically / sensibly on your feet. All they're trying to do is put you off balance and put you under pressure to see if you crumble.....don't!!
So long as you end up with a plan and you have the courage of your conviction to go with it then they'll like you. if you end up making a stupid mistake, then admit it and then suggest an alternative.
I've never had to do anything like a planning exercise in that environment and I've been in just over 4 years....you usually have others to help you and inevitably a few more than 15 minutes to come up with a plan!!!
Do show unrelenting enthusiasm on obstacle courses and all physical tests.
Do make sure you are always heard by other members of the team, even if you have to shout. Volunteer for everything in a command or leaderless task.
Re the Planning Exercise, there is nothing you can revise other than Speed-Time-Distance equations. They genuinely do use only figures that divide into 60, so there's nothing too taxing. You also get asked one speed/time question in your educational interview. Just make sure you don't flap. Have some cast-iron reasons for wanting a commission.
I only did RCB a few weeks ago, so PM if you have any specific queries about interviews, lecturettes and tasks. One last thing - find someone who has a copy of the Bleep Test on tape (old school PE teacher?), and practice it to reassure yourself: lots of people get very worried about it!
If you pass RCB with flying colours in Jan 2004, you might be n with a chance of making the Sept RMAS intake - that's the most popular intake with all the graduates. You may only be able to get on the Reserve list for Spet, even if you pass in Jan, but by applying pressure to the admin staff at Sandhurst, you might be able to squeeze yourself onto the Sept course. The May course is probably full by now. Use the time after passing RCB to visit as many Regiments as possible, even if you are signed up to the D&Ds.