that depends on several things, ammount of APs, connection speed to APs, how fast you type :)
not sure how many steps you exactly need, as mentioned read the release notes for that. but on average count of half an hour till an hour per step if you got everything we prepared. else it might be a little longer.
if you can i would do this on a quiet moment, after office hours in a weekend, ... so you got all the time to go through the steps.