i have made it from the car to the lounge in as little as 10 minutes to as long as an hour....so there is no way to answer that question....it all depends on the time & day & how busy each part of the airport is....

you have to show your ticket & id to enter the terminal building....depending on the lines this could take you anywhere from 20 seconds to 20 minutes....

check-in counters for business class should not take time but i have spent as long as 30 minutes here depending on how busy they are....

immigration & security for business class is again relatively quick....having said that, a couple of weeks ago it took me over 20 minutes to get through security as the business class line also caters to wheelchair passengers & there was one passenger who could not get off the wheelchair & a supervisor had to be called to check & allow her through....