If you que for a random dungeon to get the premium rewards (large xp and blue mail), if everyone in the group leaves but you, and you get booted out of the instance by default, you will be rewarded the full premium undaunted stuff and xp, and be allowed to que for another dungeon for the same premium rewards and xp (it will not be toned down, even if you run in the same hour). I tested this and tried to eliminate variables so did do it once accidentally yesterday, then it happened and surprised me today, and then I tested it intentionally, being left alone to be booted out, and it worked for a third time today. Ps4 NA. I will not continue to use the bug, just want to make you aware that it has happened twice accidentally to me and once intentionally while testing to see what caused it. This likely happened accidentally to many other people and may still happen (being the last to leave the group is a guarantee, everyone has to leave at some point, if you're the slowest then you're the last and you'd get to re queue).