Interaction between Power or Purpose and Sanctuary of Thought

I believe this to be a bug or maybe there is some underlying technicality that I don't understand.

Power or purpose converts 80% of your maximum mana to armor. When this is combined with passives that have benefits from your maximum mana, such as Sanctuary of thought which give 20% of maximum mana as energy shield, they are unaffected by the mana conversion. Thus, even though the mana was converted to armor, the notable takes into account the maximum mana you had before the conversion.

Sanctuary of thought also gives you 1% increased area of effect per unreserved 50 mana up to 100%. If this is the case, then why is it that when you reserve all of your mana after the conversion you cannot benefit from the increased area of effect even though you are only reserving 20% of your total maximum mana?

I believe this should act similarly to how elemental damage conversions interacts with gain effects from items like incandescent heart.

Let say for example that a character has 5000 mana. They allocate power of purpose and convert 4000 of that mana to armor. They then reserve the rest of their available mana which is the 1000 mana that is left in their available pool. This character should still benefit from the 4000 mana that was converted for the purposes of the "1% increased area of effect per unreserved 50 mana up to 100%" from sanctuary of thought since it did not get reserved.

Maybe damage related example would be more easy to get. But honestly that's the basics of conversion mechanic.

You use Ice Shot having Herald of Ash active with 100-100 phys damage bow.
– Ice short converts 60% of Physical Damage to Cold Damage
– HoA gains 15% of your Physical Damage as Extra Fire Damage

Both effects are conversions, they calculate from the same base, which is 100 phys damage. The difference is the former loses the original stuff (loses 60% of phys damage), while the latter keeps it (keeps 15% of phys damage).

So your damage would be 60% cold, 40% phys and 15% fire. 15% fire (from 100% phys), not 6% (from 40% phys).

This is why Sanctuary of Thought gives you mana based on the original value, not because the game keeps somewhere that unconverted 5000 mana. After the conversion phase, your maximum mana is 1000 and other modifiers would consider this new value.