Channel 4's strange accessibility outage

I'm puzzled by Channel 4. I don't mean their programming output, which is always puzzling, but the recent outage that wiped many of their accessibility features such as subtitling and audio description.

Apparently a fire suppression system sucked all the oxygen out of one of their server rooms, which caused a 'sonic wave' that shut down their transmission servers.

That's quite weird in the first place, but what stuns me is that the quickest way they can recover the missing services is to write them from scratch again. Channel 4 said:

These services were irretrievably lost during the incident and we won't be able to restore them until we move to the new system we are building.

What happened to their offsite backups or their disaster recovery arrangements? I find it hard to believe they don't have these things, yet an Ofcom representative said:

We remain extremely concerned by the impact on people who rely on these services. Channel 4 did not have strong backup measures in place, and it should not have taken several weeks to provide a clear, public plan and timeline for fixing the problems.

So it's true, a company the size of Channel 4 simply doesn't have sufficient backups. Presumably their IT manager is Oliver Norvell Hardy.