easiest way to export and import data between environments

Summary:

Cleanest way to export and re-import a subset of a BSO cubes content between environments (Test to Prod - recovery of a subset of data)

Content (please ensure you mask any confidential information):

So I can write a script to export data from the cube, but the result is in the Period columned format, which is less than idea to get back into PBCS.

Can anyone suggest another way, it is a single scenario for a couple of years - all periods, but the result is really too prohibitively large to spoon it back in via excel, and the client doesn't have a database I can manipulate the file with to slice / reformat it into something PBCS will natively import.