/stopcasting
/cast Unleash Elements
/click ExtraActionButton1
This is an ele specific macro, so other casters will want to replace Unleash Elements with an appropriate instant cast.
If people didn't know, clicking the button will naturally interrupt your cast and phase you out. What this macro does is the same thing, but will attempt to cast an instant if you're not under the effect of the GCD.
Eg: I'm casting a spell, but realize I won't be able to get it off before Hour of Twilight hits, I'll hit the macro. If I was outside of the GCD, then it'll cast Unleash Elements. If not, then it'll phase me out normally.
As an ele specific note, if LvB is available and FS is semi-close to finished when I come out of the phase, I will use those two back to back. With the Unleash Elements buff, it'll buff the next fire spell to HIT. So basically, I can empower my LvB hit, FS hit, and FS dot.
If you happen to have both EM and Insignia of the Corrupted Mind going, then it's sometimes worth it to replace your current FS before you lose that combination of buffs. It'll allow you to fish for more Lava Surge procs.
If you think the fight will go the full 6 minutes, use a TF spec (see Yorsahj thread, but move the point out of EQ and drop the mobility glyph). If this'll just be a 5 minute fight, might just be better off using the standard spec without Unleashed Lightning.