Apparatus and method for managing metadata in a data storage device, such as a solid-state drive (SSD). In some embodiments, a non-volatile memory (NVM) includes a population of semiconductor memory dies. The dies are connected a number of parallel channels such that less than all of the semiconductor dies are connected to each channel. A controller circuit apportions the semiconductor memory dies into a plurality of die sets, with each die set configured to store user data blocks associated with a different user. The controller circuit subsequently rearranges the dies into a different arrangement of die sets so that at least one die is migrated from a first dies set to a second die set. A map manager circuit is configured to establish an array of pointers in a memory to identify contiguous portions of map metadtata that describe user data stored in the at least one migrated die.