Comment 1 for bug 179816

If, as part of the fix for this bug, "Unknown" bugs are not changed to "Undecided" whenever a project switches to using Launchpad for bug tracking, then Launchpad could still contain bug reports with "Unknown" importance filed against projects that use Launchpad for bug tracking. Therefore, when that automatic conversion *was* implemented, the data migration would need to be done again to ensure we'd caught all the errant bug reports.

The data migration could be done just once, at that later stage, but that would leave bug reports with the wrong Importance value between now and then. It might also cause awkwardness with the Importance menu having to include "Unknown" as an option only if that was the existing importance level, and not otherwise.