When you sync now, the .DB file is wiped while the new one is built. During this time, no one can access the database.
Can I suggest that instead, the old .DB is left in place until a valid new sync is completed and a new DB is created. Then, the old DB is renamed and optionally kept (setup option) and the new valid file becomes the active one.
This would also allow for comparison of the files which might also be useful for some people.
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