This quest is marked Level 50, but I could get it at 48. I did a few of the preliminary steps and logged out. Upon logging back in, the quest had been purged from my journal. I got it again, but had to repeat the steps I had already done. Repeated this test at level 49 with same results. Perhaps it's being purged because the toon isn't level 50. Seems like either I shouldn't be able to get the quest at all, or the state as to completed steps should persist across login sessions.