When/where does Akonadi propogate contact changes?

Hello,

I have a standard Akonadi setup for kaddressbook, with contacts stored in
.local/share/contacts. Here is the situation:

-) I have made a few (minor) changes to some contacts via kaddressbook.
-) I use rsync as part of a backup script, and rsync is not detecting any
changes to any files in .local/share/contacts.
-) The .vcf files themselves do not reflect the changes made.

I have read that Akonadi is responsible for tracking changes made to its
resources and reporting these changes to interested programs, but when do these
changes actually get written to the relevant files? It has been a few days since
the changes were made; it seems like they should be been committed by now...

Thanks in advance to anyone that can shed some light on this,
MM

PS: Please CC me, as I am not subscribed.