Swiftcast Holy not instant in Garuda HN?

[Inflorescence]

Today I ran Garuda HM a few times, and was trying out Holy-ing the plumes. But while I used Swiftcast, it seemed like it still took the 5 second cast time. No casting bar appeared, but my character started hovering around in the casting animation, like it was lagging (but I wasn't).

A few things I noticed:
-Before Garuda is engaged, the skill works normally.
-If I start casting a spell during Holy's "cast time," when Holy goes off, it'll interrupt my cast.
-The bug happened about 6 times, but with 100% certainty while in the fight.
-Unfortunately, I was unable to see if the Holy counted the damage where it finally casted, or where I initially swiftcasted it. I want to say it didn't cast until after the 5 seconds, when the animation appeared.

[Lollie]

Working as intended, swiftcast only instantly casts, it does not instantly action. Holy has a longer action time the it's cast. Swiftcast allows you to release the orb immediately (no cast time) but the orb doesn't do anything until it pops, at that point you see the flying numbers. It has the greatest time difference between the 2 I am aware of making it the most noticeable. If you watch closely your stone spells do this also with a much smaller difference.

[Inflorescence]

Working as intended, swiftcast only instantly casts, it does not instantly action. Holy has a longer action time the it's cast. Swiftcast allows you to release the orb immediately (no cast time) but the orb doesn't do anything until it pops, at that point you see the flying numbers. It has the greatest time difference between the 2 I am aware of making it the most noticeable. If you watch closely your stone spells do this also with a much smaller difference.

I know what you're speaking of, and that's not what's happening. The 5 second "cast time" is before the orb even appears. Supported further by how I'm able to cast another spell that will be interrupted by Holy when it finally goes off (although this may have been from somebody running behind a pillar, but I was able to start casting it, at any rate), and how the delay doesn't go into effect until Garuda is engaged.

Also, I'm playing on a PS3, I realize that I forgot to put that in the original post.