A7sII + Can't Use IBIS with IS Lenses and Sigma MC-11

[hopkins802]

Hoping to find out if this is just me, or if everyone has this issue. When I use a lens with IS on my A7sII and MC-11, the option to use IBIS isn't available, and the message on the camera says to turn the IS on the lens on if I wish to have image stabilization. Basically, I think the IBIS on the a7sii is better (and it's silent) than the IS on my old 70-200 f/4 IS. I was hoping to just flip the IS off on the lens, then turn the IBIS on on the A7sII. No luck.

Anyone know if this is driven by the Sigma MC-11, or by the camera itself?

Thanks!
Dan