How do I go about disconnecting BitBucket? I have both Github and BitBucket set up, but after using this just a bit I really want to remove BitBucket and just go with Github (which I just subscribed to to avoid having both).
You can visit the project page at https://circleci.com/bb/:org/:project/edit and tell it to stop building.
I ended up having someone at CircleCI delete the whole account and start over.
Good to hear it was resolved for you. 
Sigh, this happened to me, too. I was logged in into the wrong account on Bitbucket. How can I disconnect Bitbucket? I deleted the Oauth token on Bitbucket already.
I’ve got the same problem and looking for solution as well.
I can only Authorize Bitbucket within Add Project tab, which gives me ability to login only with bitbucket account that I have used before. 
Could you please send an email to support@circleci.com and we’ll take care of this for you.
Thanks!
For people who are looking to do this now, you can do it without contacting support. Here’s how:
To disconnect a Bitbucket account, you’ll have to revoke access from the Bitbucket side. To do this, log into Bitbucket on the account you want disconnect (the one connected to CircleCI). Then:
- Go to “Bitbucket settings” in the lower left
- Go to OAuth under “Access Management”
- Find CircleCI and click “Revoke”
It make take a few minutes for CircleCI to pick up the changes.