I'm soon going to get my LNB swapped to the Unicable LNB GT-Sat GT-S3DCSS24.

The plan is to run feed from Unicable port to my Vu+ DUO 4K SE and have a splitter to feed both Tuner A and B.

I'll be following @Abu's guide here but curious as to why Tuner B has to be set to Connected "No" ?

Doesn't this mean that Tuner B would never be used as that is what setting implies?