Is it possible to sync photos from Office 365 back to our on-premises AD?

Currently all of our photos were uploaded directly to Office 365, and this works fine on Lync and Outlook. However, we're trying to populate our on-prem AD 'thumbnailPhoto' attribute with these photos. I've researched a bit and I haven't found anything recent that shows if this is possible. I see from the list of attributes on DirSync that 'thumbnailPhoto' is only read, not read/write. Does this mean we are out of luck to put these pictures into our on-prem AD? Are there any other methods for us to try?

These are two relevant articles that I found;

http://community.office365.com/en-us/f/613/t/62003.aspx

http://social.technet.microsoft.com/wiki/contents/articles/19901.dirsync-list-of-attributes-that-are-synced-by-the-azure-active-directory-sync-tool.aspx

Thanks, Nick