Thinking a bit more about this from a Debian perspective, the main problem is that the upstream source host wiped out all history of the project including the source code of all earlier, non-LLM versions.
I would imagine the 5.x packages can easily remain in the Debian archives, but with the effective loss of upstream code at the referenced URL this may be much closer to e.g. an old source tree vanishing from a personal hoster than anything else. Debian itself will probably have to maintain the 5.x version going forward in some fashion, if the package is important to other archive users.
