Obviously I'm new to Git and SourceTree. I used SourceTree to force-push 43 commits into our master on GitHub, and now GitHub does not show any of the commits made before the earliest of those 43, which apparently thought it was adding all of its files for the first time.
How can the GitHub repo be set back, as though this force-push never happened, or - better - so that it shows the numerous earlier commits it already knew about before this force-push?
(I've been using the force-push with another repo fine with batches of commits; the problem in this case seems to be that the commit earliest in this batch somehow thought it was an initial load, or something like that, essentially causing the master in GitHub to be reset from that point.)
There is no danger of anyone else pulling from this repo; it's private and just used as a work log at the moment, which is why it's important to get back to the earlier history.
-Ken