If I have read-only access to an org with private repos, I can create a fork from that repo and work on that as I please.

I want to be able to build that forked repo (which I own) however CircleCI does not allow this.

Creating a flat copy instead of a fork doesn't work because merging bug fixes etc.. from the source repo into my "fork" (which is a copy not an actual fork in this case) becomes extremely cumbersome.