In the docs it states that LDA " ...takes mail from anMTAand delivers it to a user's mailbox, while keeping Dovecot index files up to date." I am wondering if LMTP also interacts with the Dovecot index files and keeps them up to date?
Yes... although it doesn't seem to state that explicitly in the wiki...
http://wiki2.dovecot.org/LMTP -- Best regards, Charles