Yes, the DiSEqC option is still available when selecting a JESS switch... but then, should I enable it even if I have only 1 sat position and no DiSEqC switch?
Because in my tests (performed without the DiSEqC option activated) I was able to use only the first 2 JESS/EN50607 user bands of my multiswitch...
Sounds like a the switch is operating in a non standard way. Lots of conventional multiswitches with this issue.
Ugly.
Unicable and JESS both explicitly FORBID the use of DiSEqC on the same cable. So if some switch or LNB requires it, it's not standards-adhering.
I must say, I haven't spend a second on Unicable / DiSEqC interoperability, exactly for that reason. Yes, you can choose DiSEqC in the tuner settings, when it's Unicable enabled, but I really don't know if it actually works (or did in the past). It's a monstrosity, it's "prone to error" at the very least.
A Unicable switch (or JESS) should behave like a multiswitch and should need no additional control besides Unicable or JESS commands (like voltage, tone, tone bursts or DiSEqC) to operate.