I can confirm that this is indeed the case. If you create a new project and import databases that already exist in another project all of the history is retained across different projects.
I have however noticed that Labelling isn't maintained across projects. This is a slight oversight and can easily be remedied by modifying an existing stored procedure.
I should point out that private and public T-SQL scripts and any packages are unfortunately not currently transferable . That said, it wouldn't be difficult to perform this move by providing you with a suitable script.
As this functionality won't be difficult to include we will add this in. But if you need to perform the move prior to the new build please let me know and I will provide you with a script.
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