So I'm doing the Iron banner and finished a match with 9 out of 10 Iron Wrath. I have to leave the playlist because supper is boiling over. So I get right back into IB, get 2 kills before I die, no Iron Wrath. So I figure, well shoot, it must reset if you leave. Except that I didn't get a 10 kill streak and had to leave the playlist to take supper out and my progress (sadly only 1 out of 10 this time) is saved. So... screw you I guess Destiny. You got me.