It might want to move to another spot. When a coral inflates like that it makes it easier for it to ride the currents so to say and move around. Definitely keep an eye on it for the next few days or so. If it doesn't bounce back to normal then repositioning the coral might be the answer. GL.
Elegance are weird like this in my system as well.
I can’t discern a difference in parameters when this happens, but they seems to prefer a little higher nitrate in my system.
My phos runs around .2-.3 (not .02-.03)
And nitrates I keep em around 18-23 ish on average. Seems to be the sweet spot in my system.