After you specify a partition to use for a given snapshot, that partition cannot be changed or resized. When you delete the snapshot, the stored-on partition is also deleted.
After you specify a stored-on pool to use for a given original pool, that location is the default stored-on pool for all subsequent snapshots made of the original pool. To modify the stored-on pool that is associated with an original pool, you must delete all existing snapshots for the original pool, then begin again to create a new family of pool snapshots. Deleting all snapshots on the stored-on pool does not delete the pool itself.
To resize the stored-on pool, you can add segments to the pool to expand it just as you would for any pool. For information, see Section 16.4, Increasing the Size of a Pool.