Do you have a working zita-njbridge triplet of command lines (one n2j, two j2n) proven to run in multicast mode, which you might share?

I'd like to study a working example, to compare to my special case, where I'm running them all in one machine, with three separate JACK servers, only the first one being connected to real hardware.

I have zita-njbridge working just fine in one-to-one mode, but if I try the following triplet (SOFT1 and SOFT2 are additional JACK servers):

zita-n2j 239.255.0.10 55555 enp0s25
zita-j2n --jserv SOFT1 239.255.0.10 55555 enp0s25
ita-j2n --jserv SOFT2 239.255.0.10 55555 enp0s25

the NIC item is not reported as extra, but the second j2n is still blocked, it's still running in one-to-one mode; this is proven because if the first one is killed, the second one automatically connects. The same occurs if I run each in its own firejail, all of them being given their own IPs connected to the same dummy NIC.