I am placing BoE loot from legacy dungeons in my Guild Bank. When other characters go to check items out, some items show a very low iLevel and stats, but when I remove them from the bank, they show a much higher iLevel and stats in my inventory (e.g., item goes from iLevel 35 to iLevel 218 or something). The “useable by” level also shifts upward when that happens. The “correct” iLevel–the one displayed in my characters inventory and when worn–shows when the item is placed in my personal vault or the warband vault.