Normal
Re: CableIn your example, with 3 S16, anything you send from FOH A will of course be shifted out of existence, but you have 24 channels above the 24 S16 outputs that you could use to send something through the S16 to FOH A, thus you will have (at least) 72 channels from MON to FOH.
Re: Cable
In your example, with 3 S16, anything you send from FOH A will of course be shifted out of existence, but you have 24 channels above the 24 S16 outputs that you could use to send something through the S16 to FOH A, thus you will have (at least) 72 channels from MON to FOH.