Thanks for the extra effort! I moved the
FS_METHOD line to the position following the
WP_HOME setting, removed and re-added the site to Updraft, and tried again, but still get the error.
I tried (I don't know why I didn't do so earlier) updating WordPress plugins directly from the WordPress dashboard (in other words, not using Updraft), and also got the error there.
Here's the result of plugin update attempt:
Unpacking the update…
Installing the latest version…
Removing the old version of the plugin…
Plugin update failed.
An error occurred while updating All-in-One WP Migration: The update cannot be installed because we will be unable to copy some files. This is usually due to inconsistent file permissions. storage, storage/index.php
However, I was able to update one theme and two other plugins (all of these failed previously), so it seems that your solution had some positive effect.
I then deactivated all plugins, that didn't help. And, WordPress would not let me delete the failed plugin (but also won't let me delete some other plugins). I was able to delete the All-in-One WP Migration folder through an SSH session, though. I then re-installed All-in-One WP Migration from a backup (knowing that it would once again prompt for updating). I was able to update it from the WordPress dashboard. I was then able to deactivate and delete this instance of All-in-One WP Migration. This seemed to reinforce the likelihood that the problems I'd been experiencing were related to permissions from the initial installation.
I then used SSH to change the permission of another plugin that would not delete (all the plugins that were present had an ownership of bitnami, except for the new one I had just re-installed). By using chown to change the ownership of another plugin to daemon, I was able to delete it using the WP Dashboard.
Should the plugin folders be owned by bitnami or daemon? If the latter, I assume that they were somehow assigned to bitnami when I restored an existing site (formerly hosted elsewhere not using Bitnami) into the new Bitnami LIghtsail instance, rather than install the plugins using the WP dashboard.