I was well prepared for the interview. I ensured my Windows Server skills, GIS skills, and my working-with-councils skills were up to date. However, they asked a lot of questions that made me very suspicious internal promotion was going on, and that made me incredibly wary that I had no chance of getting the role.
Bearing in mind I had worked with councils for over 10 years and even had my own software running in councils nationwide. I knew almost all the popular GIS systems and servers and literally ran public-facing services single-handed. On top of that I was the Senior IT Manager. Not trying to blow my own trumpet too much, but I knew my stuff and I knew council stuff very well.
However, the questions I was asked were NOTHING like what was on the job description and were NOTHING like any technician or developer I know could prepare for. Most technical questions were aimed at certain unknown proprietary systems that almost nobody could use or know about unless they happened to work for, say a council that already used them. It seemed I was just there to 'satisfy the system'. As far as I know, councils are 'obliged to advertise all jobs' and not be biased even if they WANT to promote internally. However there is still a way of being biased, and that is to query knowledge at the interview stage that only internal people can hope to have.
I guessed the following might happen - and it did - a role came up for a 'Junior IT Technician' a few weeks later for the same council. Funny how a lower position just 'opened up'! The pay was pathetically low in comparison, so I didn't apply for that one, and there was of course a chance that role may have already gone to someone else.