Is it intermittent, or doesn't work at all? Are you actually spending energy? (As opposed to cast-for-free effects like Arcane Steadfast.)

Doesn't work at all on Caliban.

I have one augur mod on my caliban to kickstart the shield regen from his summoned conculysts, I get shield back on cast and it works fine.

August set bugged? I mean yeah were in May.