Multiple UR824s - more headphone mixes?

I run Cubase 9.5 pro on Windows with a UR824. Am considering purchasing a second one and daisy chaining via the ADAT ports. Aside from having 8 additional physical inputs and outputs, I also want to be able to control 4 separate physical headphone mixes. Each UR824 provides 2. By using the ADAT IN/OUT will I get that? Or does that just link the second 824’s 8-ins/8-outs? Thanks for any info - and sorry if this is a duplicate post.