Automatic Sideboard is driving me insane

I hope this is a bug and not a feature. Every game since the update it has been automatically sideboarding and it's driving me insane. I have to now instead of just sideboarding I have to go through my entire deck to see what it has decided to take out and put in. It's like you put in negates last game so obviously I need to pull out all your rares and just toss in your negates against this agro deck. I really hope this is a bug.