Mike,
How do I go about doing this? I assume that it can be done, just
doing two transfers, one after another?
That should work. In the "Go" message to the transfer agent specify exactly what content you do and do not wish to have copied.
There is a slight question about which to do first, but on the whole I think I'd say A first. The disadvantage with this is that B's messages will end up "newer" in the sense of having higher message numbers. But it means that any subscriber to A who had also contributed in B (under the same email address) will retain ownership of their content from both groups.
The disadvantage of copying B first is that without copying its subscribers the content will end up "orphaned" - no connection to a subscriber, which means only a moderator can edit or delete that content.
I suppose the best result would be to copy A's members first; then B's content, then A's content. I don't know if that result is worth imposing on Mark that much.
Assuming that transfers resume at some point...
Shal
Shal Farley