Aris Viewer and Aris Viewer Pro

Hello,

Is it technicaly mandatory to use Aris Viewer and Aris Viewer Pro with both "named" only or "concurent" only ?

Can we use "concurent" Aris viewer with "named" Aris  Viewer Pro ?

We used to have Aris contributor in named with Aris viewer concurent licences.

We have been told that Aris  Viewer Pro has replaced  Aris contributor licence.

Thanks

Omar