Backup and restore appset for migration BPC 7.5 to BPC 10.0 mandatory

Hi,

As a strategy to migrate BPC 7.5 NW to BPC 10.0 NW,we would be copying "BW PROD BOX 7.0 " to "BW QA 7.0" and then migrate it to "BW QA 7.3".

However,in  "How to migrate BPC 7.5 to BPC 10.0",it suggests to backup and restore before executing  migration program.

But as we are copying the Server "BW PROD 7.0" to "BW QA 7.0",BPC 7.5 appset would have also been copied to BW QA server  and must be available for migration..

So is it MANDATORY to take back up of APPSET in PROD 7.5 and restore in in QA 10.0 system?or we could skip this step and run migration?Could you please suggest?

Regards,

Pradnya