Systems and processes for migration of data stored in a label-based software configuration management (CM) system to records of a time-based CM system in a manner that permits for identification, in the time-based system, of contents of releases. In some exemplary implementations, techniques operating according to some of the principles described herein will accept as input information relating to a listing of a label-based system and estimate, based on the software component versions in the listing and their corresponding creation times, a release time indicating a time a release was created. The release time may then be used, in some, but not necessarily all, implementations to create a data structure in the time-based system indicating contents of the version at the particular time. Some exemplary implementations may additionally determine, from the estimated release time, whether any software component versions should be explicitly included or excluded from the data structure.