imap-backup mirror SOURCE_EMAIL DESTINATION_EMAILThis command makes a local copy of the emails in the source account and then copies them to the destination account.
Exactly which folders are backed up (and mirrored) depends on how the account is set up.
Specifically, the folder inclusion mode (whitelist/blacklist) and
folders to include/exclude list.
Note that, anything on the destination account that is not on the source account gets deleted.
--source-delimiter- the separator between the elements of folders names on the source server, defaults to/,--source-prefix- optionally, a prefix element to remove from the name of source folders,--destination-delimiter- the separator between the elements of folder names on the destination server, defaults to/,--destination-prefix- optionally, a prefix element to add before names on the destination server,--automatic-namespaces- works out the 4 parameters above by querying the source and destination IMAP servers.
If the local copy is in 'keep all' mode, the destination account will gradually have more and more emails.
On the other hand, if the local copy is in 'mirror' mode, the destination account will have the same emails as the source account.
For details of the delimiter and prefix options, see the note about delimiters and prefixes.