No, you're forced into the A/B test. I assume they'll enable this on every account at some point. Maybe there's a way to edit your account's flags via some undocumented API endpoint, but I'm not sure. Even if that were possible, your account would likely be flagged for API abuse and banned within the day.

It's been patched now, so if your account wasn't already stolen, you're fine, at least for the time being.