Never call it a 'license' (or 'licence', if you prefer) around the FAA. It's a 'certificate'. They get rather sniffy about that sort of thing. Even we Yanks make that error, but they still don't like it.
I have a friend who recently finished the program with Envoy and is now flying right seat for them in the ERJ-something or other. He was a typical naval helicopter / civil helicopter guy with a couple hundred hours of fixed-wing time. He got his ME rating and built the few dozen hours he needed to tick off the boxes for the ATP and then he was off to his type course and onto the line. Took him a couple of months for each bit, perhaps 6 months in total.