With a combination of princess, diplomat and actions from another player, you are able to have 2 queens in the game(atleast).

Your diplomat starts moving your queen back when its captured instantly. Then the other player sends drillers to defeat the queen being transported back. Now your princess turns into a queen and your queen turns captured while still traveling towards your base. When it arrives, you now have 2 queens. Both give the extra amount of shields and have a possibility to hire a specialist. You will still get the same amount of specialist but can decide which queen you get them from. Here's a short video of it in action.

Vid (Edit: Made video private, will turn it on when the game ends.)

Thanks for your report. I've forwarded it to the devs. They'll be able to watch your game and reproduce this.
If your username isn't enough to find the game you're in, they might ask you for the game name.

That double queen was terrible to play against.

I have the screen shots right here! Was thinking of posting this little bug myself.

Oh my god the captions to those pictures made my day.

Interesting... Thats how it happened...

Lol at captions