dovecot - Dec 2017 - rename dirs at file system to strip .INBOX prefix?

looking at my personal email in
/var/vmail/vmail1/dom.tld/voytek at dom.tld/Maildir

I have some older dirs prefixed with .INBOX as so:

.INBOX.Sent.2010.11
.INBOX.Sent.2010.12

around 30 or so, every other dir, .Sent or otherwise, doesn't have INBOX
prefix

can I just rename them from terminal to strip .INBOX from dir name..?

and, if I do, what else I need to do

or is that a bad idea, if so, how to get rid of old '.INBOX' prefixes?

thanks,
-- 
Voytek