the whole new upstream operation is aborted,
except for the laundering.
+<new-version>
+may be whole new Debian version, including revision,
+or just the upstream part,
+in which case -1 will be appended
+to make the new Debian version.
+
The <upstream-details> are, optionally, in order:
=over
but if this situation is true and expected,
forcing it is fine.
+git-debrebase will try to look for the dgit archive view
+of the most recent release,
+and if it finds it will make a pseduomerge so that
+your new git-debrebase view is appropriately fast forward.
+
The result is a well-formed git-debrebase interchange branch.
The result is also fast-forward from the gbp branch.
+It is a snag if the new branch looks like it will have diverged,
+just as for a laundering/unstitching call to git-debrebase;
+See L</Establish the current branch's ffq-prev>, below.
+
Note that it is dangerous not to know whether you are
dealing with a gbp patches-unappled branch containing quilt patches,
or a git-debrebase interchange branch.