Unreachable Dig flag is sometimes not removed.

I can confirm this, plan a bigger build with stuff not reachable and sometimes it says it is not reachable even though it is dug out.

I have the same issue: I need to manually force duplicants to move there to move the build forward - cancelling build and build it a new - creates the job as reachable, the duplicants starts the job then they leave it and it becomes unreachable. This bug has devastated my game ;/ (run out of water)