EO is simply a grade in the civil service, not a job description. It can be lots of different jobs, depending on the department. It's not always called EO, even, although every department will have something at that level.
Before deciding whether or not to go for it, ask to see the job description, and the salary range, because these vary across departments, too. There might even be allowances attached to particular EO jobs, for different responsibilities.
I know that doesn't necessarily sound helpful, but there really is not a straightforward answer.
Bear in mind, also, though, that the civil service still has one of the best pension schemes going, and that many other of the terms and conditions are also pretty good compared to being at temp!
If you actually want any serious advice about the job, PM me, preferably with a link to a specific job description.