Original title: Migration weirdness (SO->SU, SO->SF->SU)
A duplicate migration happened. A question was posted to SO 22hrs ago; it was soon migrated to SU; it was migrated again to SF, either around the same time or 20hrs later; SF migrated it to SU around 2hrs ago.
Here's the apparent timeline:
Is the double-migration from SO due to a known bug, something new, or accidental double-migration?
Edit: OK, the revisions links show the UTC times so we can trace the timeline correctly. SO migrated the question to SF first, then an SO mod reopened and migrated the question to SU. Finally SF migrated their copy to SU. I'm fairly confident this is a reasonable interpretation and thus not a bug.
Question:
Is there anything we mods can/should do to avoid this sort of thing in the future? For this example, should the SO mod have flagged the SF version for the SF mods to delete?