Passive Energy Regen does not work while casting non-channeled abilities

[TheToasterOven]

I think I've noticed this bug before but this is definitive proof that passive energy regen (or at the very least, Exodia Brave's passive energy) does not work while casting abilities, even if they are not channeled. As you can see in this gif, I have Bastille which costs 25 energy to use, I "start" with 100 energy, get a triple which maxes out Exodia Brave, then wait for the buff to end without casting anything and I receive the full 60 energy. However, I then repeat the process, "start" with 110 energy, get a triple kill which maxes out Exodia Brave, instead of doing nothing I throw three bastilles out during the energy buff. 110 starting energy - 75 bastille energy consumed + 60 arcane energy restored, should equal 95 energy after this. However as you can see, I am left with 51 energy instead. I've tested this lightly with other methods of passive energy restore (such as voracious metastasis) and it's all been the same result. This used to not be the case but I believe with a "recent" patch (I haven't played too much since the new war came out) energy now drains in a new way where every ability is actually channeled until it finishes casting. https://gfycat.com/secretsoulfulanaconda