Starting Weston drm-backend from non-seat0 ?

[nerdopolis]

Hi

I found out how to get the systemd session-seat to be my desired seat (with
--setenv=XDG_SEAT=seatx of which pam_systemd.so responds to) After assigning 
devices to the seat, and trying to start it I get "logind: session not running 
on a VT"
Of which is a bit confusing as as far as I understand, VTs only work for seat0.
Trying to start it on a tty with the XDG_SEAT and TTYPath results in a failure 
that seatx is not seat0)

Is there something I am missing?

Thanks