migrating emails downloaded to zoho via pop3

migrating emails downloaded to zoho via pop3

This account has several pop3 accounts configured to download email and delete from the host server. So the only existing copies of these emails are in zoho. I'd like to migrate them to another host.

According to this thread I can't get IMAP access to the other pop3 accounts. So while I think I can download these emails as files (havent tried) The new provider only allows migration from IMAP.

The thread linked above suggests forwarding emails from the pop3 account to the primary zoho account. But given that these emails have already been received, it appears the only way to do that would be to forward the emails inline, one by one. An impractical solution given that we're talking about around 2gb of mail.

Can support offer any alternative? Can you transfer mail folders from the pop3 accounts to my primary zoho account en masse so I can get at them via IMAP?