questions about maildir to mdbox migration

[Dave McGuire]

  Hi folks!  I converted some of the spools on my mail server from
maildir to mdbox.  It went smoothly and the performance has been great.
However, I have two questions regarding the process.

  First, I failed to notice the fairly low default mdbox_rotate_size,
and I changed it in dovecot.conf after the migration.  Is it possible to
somehow make that change retroactive, to coalesce the couple thousand
"storage/m.*" files that are anywhere from a few hundred bytes up to a
few megabytes, into a smaller number of larger files, without re-doing
the migration?

  Second, I'd like to delete the old maildir files and directories to
reclaim the space in the filesystem, but it's not clear to me which ones
I can safely delete, i.e. ones upon which my new mdbox-based spools no
longer depend.  I know maildir uses new, tmp, and cur directories, but
in the spool directory there are also files like dovecot-uidlist,
dovecot-uidvalidity, dovecot.index.cache, dovecot.index.log,
dovecot.mailbox.log, as well as separate directories for each of my mail
folders containing their own new, tmp, and cur directories and their own
dovecot* files.  Can someone offer some guidance regarding which ones I
can safely remove?

            Thanks,
            -Dave

-- 
Dave McGuire, AK4HZ
New Kensington, PA