Thanks for posting and just to let you know I've moved your post to an existing thread under App changed when in Premium Access session.
It looks like you're subscribed to Pandora Plus, not Premium. However, you're receiving a prompt to watch an ad because you've activated Premium access which unlocks additional Premium features like on-demand content. In the past, free listeners and Plus subscribers were only able to look for artists and tracks in order to create radio stations. Now, if you search for and select the name of an artist, track, or album, you'll be brought to a "backstage page" where you can either create a radio station OR press play. If you press play you indicate that you'd like to listen to that content right away (or "on-demand"). Since on-demand listening is a feature for Premium subscribers, you will either see an ad for Premium, or be prompted to watch a video ad to unlock Premium access.
If you don't want to listen to music on demand and avoid the ad, just start a station and it will prompt you to that artist or music station.
For more information or tips about Premium access sessions, please check out this thread: Tanner's Tips: #2 Premium Sessions
Hope this helps!
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