Partitions For Archiving - Date With Completed Flag?

I am working on an archiving strategy. I want to roll off transactions that are older than seven days, but only if they are flagged as Completed. The numbers of transactions are very large so this is a worthwhile venture.

The only strategy I have been able to come up with so far is to partiton on date. Then when 7 days comes up, sweep the about-to-be archived day for the few remaining not Completed transactions, put those into a new table (a new version of this partiton) and switch partitions. Each day I do this until the older parititions are empty.