Went in May, and our biggest issue was the US customs hall. Only 4 of the booths were staffed, and it took over an hour to get through. We sprinted to our flights just in time for the doors to close - we overheard many in line who had already missed theirs. I haven't seen much mention of the US customs section in all of the articles about improved staffing etc... I would say this: don't delay at all after getting off your flight from Calgary. Use the washroom during descent if you can. If not, head straight to security/customs and save any food or washroom breaks for AFTER.