No Boss Atlas Skill Book Drop

I have all 40 Atlas Points.

I completed a T15 Boss map and had the Skill Book drop to get my first 2 Boss Atlas Points.

I have since completed 2 T15 Irradiated Boss Maps (L80), and a T16 Corrupted WS and Irradiated (L81) Boss map with no further Skill Books dropping.

There are quite a lot of similar threads, but wanted to make sure it is still known that this Bug exists.