It usually takes few hours to update.
Firstly, The contest has hacking round ~12hours, Then system checking <=3hours
After system checking, final standings are published.
So in total it take 16hours to 24hours to update your rating on your profile. (Sometimes it also takes more than 24hours, but surely changes within 36hours)
Thanks for reading. Please correct me in comments, if I am wrong.
Well it can take more than that too.
Like the ratings for yesterday's contest are still not updated even after more than 24 hours.
Its updated finally...After approx. 25 hours since the end of the contest.
Well until then you can see your predicted rating here.
does this link still work ?
waiting........