Comment 9 for bug 1528583

I've been testing the packages as we work on them, ironing out issues with upgrading from both 5.5 and 5.6 as we go (I'll need to rerun these tests for the currently uploaded package, though).
But I've only been testing on Xenial, i.e. installing 5.5/5.6 then replacing with 5.7, so I haven't done anything with testing the full upgrade from previous Ubuntu releases.
I've also not done much with testing custom configurations and databases with any significant amount of data in them.