Larian Studios Forums Divinity: Original Sin 2 Divinity - Original Sin 2 - Bugs & Technical Problems [Bug] Can't Cast Elemental Affinity Reduced Spell

I just reproduced it exactly as I wrote in my OP.

It appears to be how it interacts with Phoenix Dive. If you have 2 AP and then cast Phoenix Dive, you will have 1 AP left and be on a fiery surface. Your tooltip will correctly say you are affected by EA, and the tooltip cost will state the spells cost 1 AP. However, you cannot use those abilities - they will be grayed out, and pressing their hotkey will not initiate the spell.

Further, the "bonus bug" is reproducible if you cast Phoenix Dive while being affected by EA on an Earth surface. (i.e. you had the AP to cast it while being affected by EA before you dived, but not after).

Uploading the save will do you no good. When you reload the save, the spells are available as they should be. But I just did this 5x in different ways to make sure of it.