Show ads in channel first, remnant last

I am porting an existing site to Drupal and want to keep as much functionality as I can.
The present site has many topics. It has 15 ads shown in the right sidebar. Each ad is assigned to one or more topics. When a topic is chosen, ads related to the topic are shown first, and then any other ads are shown to complete the 15.
I thought I could accomplish this with ad_channel, but ads are mixed and shown in random order. It is important that topic ads are shown first! This is what was promised when the ads where sold and how it works now.
If I mark ad as premiere other ads are not shown.
Is there an easy way to accomplish this?

Thanks.