Only had my ST for 3 days now. Yesterday I updated SYNC 3.4 to Build 20136 via USB from Ford's site. Took about 25 minutes once USB was plugged into the cars port.
Today I loaded Maps NA 1 19 via USB from Ford's site. They said about an hour to install once plugged into the car. 1 hour and 27 minutes. It's a good thing I am patient.
This is not my first dance with these updates. I updated my 2019 Ranger a month ago, much bigger PITA than the ST (BTW I sacrificed the Ranger for the ST) and I updated the maps in my 2017 Mustang GT when I did the Ranger.
I'm still pissed that I had to shell out $150.00 for the maps for the Mustang! When it's time to update them again in the Mustang, I'm saying screw it and getting a GARMIN with lifetime map and updates for the same money or less...