I don't go to Aidans, but you are likely to be notified upon arrival and given adequate time to get ready for any themed events. Whatever happens, you'll be in the same boat as everyone else, which is where you want to be.
thats the beauty of freshers week! Everyone in the same position. Meet as many people as you can!! The 'Wood get notified beforehand of a rough schedule - rob you should know, you are a rep after all - but i wouldn't be surprised if you can find it all on the JCR website. Have a look and see nearer the time. Things don't really kick off til after the 17th.