Several embodiments of the present invention comprise a storage platform that provides a synchronization service that (i) allows multiple instances of the storage platform (each with its own data store) to synchronize parts of their content according to a flexible set of rules, and (ii) provides an infrastructure for third parties to synchronize the data store of the storage platform of the present invention with with other data sources that implement proprietary protocols. However, it is possible that a conflict might arise in a number of synchronization scenarios. For example, A1 and B2 may have been changes made to the same change unit, or A1 might be a deletion to the same change unit that B2 was modifying. While some of these conflicts can be resolved using the conflict resolution options discussed earlier herein, certain conflicts provide particularly difficult challenges, and these challenges and their solutions are discussed herein.