I'm in the same FC of Clef, and yep what we tried so far isn't fair at all for a group of 4 or more ppl.
If you play and join the frontline alone, the queue is really fast like 5-7 mins Max.
But if you make a group of 4 or more ppl (you know this is an MMO and is supposed to play together with other people), then the wait is very long! it can even reach 50 or more mins to join a Frontline.

And what's even more annoying is the fact that if someone try to join the queue ALONE 30 minutes after us, then he/she will enter the Frontline before us!!!