Comment 24 for bug 1640978

I'm confused on a couple of points. Here's my understanding:

AFAICT, there are three source packages in play here: src:python-acme, src:python-letsencrypt, and src:python-certbot.

src:python-acme appears relatively straightforward. A version bump is needed for new features used by this proposed update, but there is no other package renaming going on.

src:python-certbot supersedes src:python-letsencrypt, though of course apt doesn't see that.

src:python-letsencrypt created binaries letsencrypt, python-letsencrypt and python-letsencrypt-doc in Xenial. It doesn't exist in Yakkety or Zesty.

src:python-certbot creates binaries letsencrypt (transitional to certbot), certbot, python-certbot and python-certbot-doc from Yakkety onwards, and doesn't currently exist in Xenial.

The proposed backport of src:python-certbot to Xenial makes some backport-related dependency changes (so it seems) but I don't see anything that changes the structure of package names or transitional packages from what is in sid (and Yakkety, etc).

So to my questions:

1) What happens to a Xenial user who is using the library provided by python-letsencrypt after this update? Is it intentional that src:python-letsencrypt in Xenial will continue to provide it?

2) This is more of a question for an archive admin. Is it acceptable in Xenial for src:python-certbot to take over the letsencrypt binary name, but for us to retain src:python-letsencrypt that also produces it?

3) What happens if a future update (say a security update) is needed against src:python-letsencrypt for users still using the python-letsencrypt binary package in Xenial (from question 1)? This update would still produce the letsencrypt binary, but we'd have a higher version from src:python-certbot in the archive. So would the subsequent binary upload fail?

Does this mean that we also need to SRU src:python-letsencrypt at the same time to stop producing the letsencrypt binary package at the same time?

This is for Xenial only. I haven't considered Yakkety yet, nor have I completed my review since I want to understand and fix this point before considering any other further interactions (which may change if we change how we're doing this here).