I was told by Meridian rep in late february that I could run a height layer with the same feeds as in 7.x for a better sound bubble.

He said this configuration of 7 x 2 = 14 will always be supported. (L C R SR SL BR BL).

If you want to build something now run two cat7 to the height speakers. One that goes to the corresponding floor speaker for bridging that audio feed. And one to the 861 processor for later use when 861vX upgrade is available.

Meridian is using this interim layout in their demonstration theater I believe.

DSP8000SE, DSP7200SEHC, DSP5200SE sides, DSP7200SE rears, 861v8, 210, Sim2 Ultranero 4, Stewart Cinecurve 2.35:1, XEIT CM-5E Anamorphic lens, Dune HD Duo Cinema 8K and Wireworld Platinum 48G HDMI -> UHD722 -> Shunyata Omega Ethernet. Shunyata/Furutech power-cables/filters. SR Master Fuse@861v8. Uptone Etherregen with 10MHz OCXO clock.