I don't know if this is going to be of any use but for any new entrants wanting to join the Grade:
READ THE INSTRUCTIONS ON THE JOB APPLICATION/ ASSESSMENT CAREFULLY. The external application will give you an idea of the base salary, although O/T and Sundays can add up to 10% on top do not plan your life around that. I am still surprised after many years how many people still budget on the extra cash, it really isn't a good idea to do so (and yes, I used to fall into this trap). Other notes from this thread are:
1. DO NOT Take Simsig as gospel.
2. I would strongly advise you NOT to read the rule book. The assumption is for external applicants that they know f*** all about the railway in terms of in depth operations. That is what signalling school is for, to teach you the nuts and bolts. However if you show a general interest in what NR does and how it operates then it will stand you good stead.
3. The HR process is long, time consuming and exasperating. The staged process and sifting is (as clear on the thread) like the proverbial circles of hell. However once the positive decision has been made they will let you know, whether that be for interview or at the end of the interview a job offer. However be warned that NR as an organisation can be cumbersome and change it's mind in regards to vacancies. And HR are only one part of the process, the hiring managers are those at the end of the day are those responsible. Internal applicants find the process very frustrating, so I have sympathy.
I would also take time before starting the process to note how many Non technical skills you have acquired an how they can be applied. As a side note I would add the computer is looking for consistency.
Apropos to the above don't waste time sweating once you have hit the submit button/ been through the interview. I know it is nerve racking and can be quite frustrating but what has done has been done - you can't undo it. Go out and live your life - don't forget that (based on the lift test etc etc) there will be plenty of opportunities to apply again if your life's desire is to join the grade. As is plain in this thread several people have applied multiple times, NR actually gives you the tools on it's website to assist you if you fall at certain hurdles (i.e how to put a CV together).
4. There are other ways into the signalling grade. One way is via a job such as Trust Delay Attribution as mentioned above. It is also easier to get into the grade from a "railway job" - i.e look for a job with a train operator and then apply (I joined from Wessex Trains many many moons ago).
5. If you have been offered a job- congratulations! They will let you know regarding the Signalling school etc. There is the obligatory medical to undertake but as long as you are generally fit there should be no problems, although do not have a drink the night before. I know of now ex signallers who on the day before their booked medicals have been out for a few jars/ glass of wine, only to fail the next day..In regards to signalling schools, places are limited and your LOM will supply you with tickets and hopefully the background bits required for your time on the course. My advice will be to join the Union ASAP as well. I have no truck with the politics of the RMT however the background stuff is useful and a good Rep is worth their weight in gold. It is a pretty intense course so (as mentioned above) on your downtime use it as downtime. Do the work which the trainers ask you to do and remember that the NR's drinkndrugs policy applies. Also ask questions, lots and lots of questions if you are unsure of any particular point of principle.