It never ceases to amaze me the number of top level organisations who do not regard SSL certificates as a critical asset and will allow issues like this to occur.
If this is indeed true, and it fits from my experience (only Storage can take everything offline for nearly 3 days, with complex VLAN Networking problems second.) Then it looks like this was not a well engineered solution, or alternatively hit bugs in the XIV Storage Array which they needed to get programmers to resolve.
If the comment from Computer World is true, then I would have expected IBM to have a second XIV Storage Array which they would have been doing snapshots to, and could have failed over to, before they did the hardware upgrade on the primary XIV Storage array, then after testing they could have fallen back to the primary and upgraded the secondary array.
It appears IBM only run 1 storage XIV SAN Array in that case.
I know of clients in the graphics industry which buy two of these for exactly these reasons, so if IBM didn't have a second one you wonder how cheap they really are.
This is of course all speculation - as I have no insider information, just experience working on a range of SAN's.