Most of the SEP instructors are retired or former crew. Their job is mainly to train and certify that the crew,both cabin and technical crew are fit and able to operate the flights. This is a good job for ex crew as the salaries are quite attractive. They are daily paid and can choose to work the number of days in a month. Some prefer to work about 2 weeks in a month and the airline would accommodate such requests. They used to be paid $100 a day a few years ago but I understand it has gone up to $270 a day. They usually work from Monday to Friday but at times they may be needed to work on weekends too.