Horde to Squirrel Mail Migration


I am needing to migrate a significant number of email accounts from a server running horde to a separate server using squirrel mail. From what I have been reading, it seems as though if I configure the accounts imap settings correctly, their inboxes (mailbox entirety?) should get pulled into squirrelmail without issue. If I could get some confirmation and direction on this it would be greatly appreciated.

Thanks in advance,