Migrating IMAP accounts
imapsync --host1 src-host --user1 src-user --password1 src-pw \
--host2 dest-host --user2 dest-user --password2 dest-pw
Official imapsync migration tool ( release 2.290 )
Imapsync is an IMAP sync tool. It syncs all folders from one mailbox to another, both anywhere on the Internet or in your local network.

Backing up IMAP accounts
GitHub - joeyates/imap-backup: Backup and Migrate IMAP Email Accounts
Backup and Migrate IMAP Email Accounts. Contribute to joeyates/imap-backup development by creating an account on GitHub.