Comment 9 for bug 1848248

So I'm surprised we have those agent binaries published for an unreleased juju. This I think is what's breaking things. Normally:

the snap will look for published binaries and use those if found
if not, it will used the jujud in the snap

The fact that we appear to have published as a one off 2.7 beta1 binaries means that we will use those stale binaries by mistake in preference to the correct jujud.