Headphone monitoring with 2 MR816X units

Hi all,
When daisy chaining 2 MR816X units, do you get headphone monitoring of all 16 channels through the headphone outs of both units? Or does the slave unit only give you its own 8 channels?

If you hook up the second MR816 via adat, you can have seperate mixes for all 4 headphone outs.

Thanks, watched some very useful tutorials on YouTube last week. Got the control room figured out now!