Knowing the way the system works, I suspect she was told that she no longer had a career after that stunt she pulled at the Select Committee hearing (together with a few other run-ins with ministers she's apparently had during her time at DECC). There's a bit of a surfeit of senior civil servants following the cuts of the last couple of years (hence one reason why I'm retired!) and the competition for top jobs is correspondingly pretty tough. My guess is that she was told there wouldn't be another senior post available for her, and since the time that I retired early the rules have changed to stop people getting anything like the deal I received. She was pretty much forced to resign, I suspect, to avoid the publicity of being called to account for her actions. I'm sure the deal she's been given is that she'll get a decent reference if she just resigns without a fuss, so allowing her to get a job somewhere else.