My youngest runs the local hot glove team, they work hands on live on the 11 and 33kV network. NG (old WPD) have something like 34 of these teams accross the country each consisting of 3 or 4 people. Pretty sure that you can't just apply to become part of a hot glove team as a 16 year old.
My son's route was to apply for a then WPD apprenticeship, there were something like 1500 applicants for 30 or so places accross the country, he was accepted as an apprentice linesman. Think it too him 3 years to qualify. During the training the wages weren't great but better than a lot of apprenticeships in other industries.
His basic work week is an 8-4.30 day plus standbys for evenings and weekends (paid for just being on standby whether called out or not). During bad storme etc they work ridiculous hours, many consecutive days with barely any sleep.
Pretty sure that all the linesman work on the HV network but not live, one of my son's responsibilities is to issue permits to work on the network, ensuring that the section to be worked on is isolated, coordinating this with central control and making sure that there are also local measures in place to ensure safety if somehow the network becomes reenergised by accident.
Another route into NG is to apply to become a 'mate'. Probably what would be called being a labourer in other trades, less pay but if you can prove yourself to be competent and willing you can progress this way. However the structure has got far more corporate of late and qualifications are expected for any of the more senior roles. Being old school I regard the apprenticeship route as the best method to obtain these qualifications coupled with on the job specialist courses,
