Media migration from LTO-3 and 4 to T10K-C. What's the *best* way given this situation?

 Hey all.

This little community board seems really active and healthy. Good to see. I thought I'd post here as there are a few vocal folks.

I've got a bit of a media migration puzzle to solve. It's a touch complicated because of the historic archiving setup, I suppose.

The setup:

1. I've got two sites hanging off the one MDS, using multiple QFS clients. Nothing unusual there.

2. It's a three copy architecture, notionally. One copy on dk/disk VSN and two copies on tape. One copy of the tape data lives in silo A. The other in silo B. 

3. Here is the kicker. Both media pools are being used by both sites in the archiver.cmd setup. I.e - Site A's filesystems arch copy 2 into tape silo A, then the copy 3 data into Silo B. Site B's filesystems arch copy 2 into tape silo B, then copy 3 data into Silo A. [Inverse from each other]