I think the benefits aren't delivered until your friend is actually subscribed, which doesn't count the first 30 day free-play period. That does mean the 'Friendship Circlet' for EXP boost will not be very useful for their main class, as they'll almost certainly be well over lv 25 by the time 30 days is up. Now... I'm not sure if the rewards come at the start of the real 30 day sub or after the first 30 days of actual subscription. I'm about to find out though, as much actual sub kicks into day since my 30 day 'free' period is up. At least the circlet will be useful for leveling up other classes.

It's silly, because the 30 day free period came as part of buying the game. It's not really free at all! We should get credit for it! I'll be patient ...