Current version of software has some internal core already designed with mind
of multiaccess (multiple clients).
I can tell you that during this week I will check if we are able to signal
that tuner is occupied (the only way in DLNA is to do it inside service
signalling part. Something like if tuner is occupied, then second
client get zero services in browser, or only one service named "Device is busy"
or something like that.).
Our steps toward full multiaacess support are as following:
1, support concurrent access to the same service (so second, third, ... client
see only currently transmitted service in browser)
2, support access to all services on the same frequency (on satellite
it means one transponder, on terestrial/cable it means one multiplex)
If things go right way, we are going to work on first step very soon
(I hope nobody kills me if I write in 2-3 weeks

) and week later
we can continue on second step. All is only the matter of coordination
of works on most important (that is "user most prefered") features first.
/Honza