I think the idea is not to give away something that can create a permanent class of free play part timers. Who know when they create a free trial account every few months, it lasts up to a month. Or a new one every tour. They will have a highly competitive late war ride waiting for them next time they get the itch and come into town. In the old days you sold cut rate drinks down stairs with girls walking around keeping company but, the girls up stairs were full price for more than a chat. Here in the USA and in Europe and the Common Wealth. Probably why Hitech keeps it to two weeks in the MA. Even FPS games follow that down stairs, up stairs rule with lots of smoke and mirrors, and why they are really freemium.
I wonder how many would admit if Hitech did a 30 day trial account where the P51D was the bird, they would cancel their accounts and play when they really got the itch knowing a late war ride would be available for 30 days? Any speculation on how the numbers would drop off as a result? Or is that Hitech's headache to work out. It's so easy to spend other peoples money until it runs out.