Hi Charmaster, on DevUI, the first Pokemon is put to active spot regardless of the turn. Benching Pokemon can only be done on a player’s turn.
Have you read this topic Help out TCG One By Testing New Cards and Bug Fixes ?
If you commit to testing and revalidating bug reports, you can get tester title too. More info for bug reports: How to Report (and Resolve) Bugs
You may also send me a DM here.