How to accept your king's offer?

Hiya!! I will be starting university in September doing Political Economy BA/BSc at KCL, and on king's apply it says (around the lines of)
"Once you've accepted our offer through an email we've sent to you, you can pay the tuition fees for this year"
Was just wondering, are there any king's students who remember how long it took for them to receive that email? and does anyone remember how much time you have to pay until the deadline approaches?
Also, was just wondering who else is doing political economy...
Thank you, and i hope you have a lovely day ))