I would say if an employer requires you to be on the premises to get "ready for work" then you should be paid for this time, most people can turn up for work and start straight away. if your contract requires you to be at work at 7.45am then you should be paid from that time, its unreasonable for your employer to expect you to work for 15 mins per day unpaid. if you add that time up your losing out on a lot fo pay. if your start time is 8am then you should be within your rights to turn up then and start from that time. are you in a union? i would be asking for proper legal advice from them if you are. hard for us to give aproper answer without knowing what your contract states. if you need to be there for a briefing then any briefings should take place in the employers time not yours.