+Various valid long-term desireable situations coexist, and while discussing immediate countermeasures, it is useful to keep the long-term outcome that those are most likely to produce.
+
+These are three possible situations for the fleet of bullseye (buster + 1) hosts:
+
+* `none`: "merged `/usr`" has been reverted; no bullseye hosts have `/{bin,sbin,lib}/`→ `/usr/{bin,sbin,lib}/` symlinks; only `cat` only exists at `/bin/cat`;
+* `weak`: bullseye hosts can have any of "merged `/usr`" or "classical" directory schemes; official packages are only built on "classical" directory schemes; packages built on "merged `/usr`" are allowed to break on "classical" directory schemes.
+* `hard`: bullseye hosts can have any of "merged `/usr`" or "classical" directory schemes; official packages are built on either "merged `/usr`" or "classical" directory schemes; packages built on either are forbidden to break on either directory schemes.
+* `all`: bullseyes hosts all have "merged `/usr`"; official packages are built on "merged `/usr`"; packages built on "classical" directory schemes are allowed to break on "classical" directory schemes.
+
+## Immediate actions
+
+Given that hosts with different top-level directory schemes already exist; there are various ways forward that would allow for Debian to converge to a desireable situation: