BOSS DROPS IS CHANGED?

Does the boss drops change? HOWA is didn't see in difficult 1 and the lowest item level on trade site is 82. Also does the life flask of olroth can get in difficult 1 since item level lowest on trade site is 81? If there is a change, where I can read about this?

The bosses all drop the same items, but the restrictions for what drops at what tier of difficulty were changed.

Now all tiers can drop any of the bosses uniques and higher tiers have higher chances of dropping the rarer items.