The addon is going to add a complete export and import solution.
There can not be a specific date as we work with the community on beta testing first. We add things and shape the tool up to its final stage then. We really want to have first working demo in the next 10 days, but the complete release couple months later.
PS: ATUM saves its data into its own table so if you have dB knowledge, you may do import from there.
Hope this helps.
Pavel