Comment 1 for bug 1919246

We need to use hookenv.atstart() to get flags set before the main reactive loop kicks off. However, I see no reason the refresh has to run every update-status hook; it is setting the snap.refresh-available.* flags, but they can just as easily be several hours out of date as they can be 5 minutes out of date. I suspect these flags are just a bad idea and not being used.

We do want to do an unconditional refresh in the upgrade-charm hook, in case channels etc. defined in layer.yaml have changed.

I'm thinking the way forward is a layer.yaml option, enable_refresh_flags, defaulting to False, which simply causes check_refresh_available to do nothing. While backwards incompatible, it is a simple enough tweak by the charm author to turn back on if they are actually using the feature.