I thought you might be interested in looking at Clients can only use 'group channel', why ?!.
https://forums.bohemia.net/forums/topic/73459-clients-can-only-use-group-channel-why/?do=findComment&comment=1308092
× Pasted as rich text. Restore formatting
Only 75 emoji are allowed.
× Your link has been automatically embedded. Display as a link instead
× Your previous content has been restored. Clear editor
× You cannot paste images directly. Upload or insert images from URL.