What happens after results day?

Hi, so what is the process for what happens between getting our results and turning up at the uni for Freshers Week? I know we will get a confirmation letter from UCAS, but what/how many forms will the university send to us before we get there, and when? Also, I know we have to reply to our accommodation offer within seven days, but is this all done online or do they send us paper forms by post to fill in and send back.
Basically, I am asking because I am going abroad on holiday a week after results day and not coming back until two days before the accommodation contract starts. So after results day, is a week long enough for me to receive and reply to any forms from both UCAS and the university ready for me to just turn up on the day that my accommodation contract starts, or do they require replies to things during the first two weeks of September? Is my 3 week holiday abroad with no internet access from a week after results day until two days before fresher's week a bad idea??

I'll give this a bump, since I am interested to know how all this works too!