With an 'A' licence you don't get types. After you have been deemed competent you will be given company approvals for the tasks that you are able to self certify eg. wheel change, filaments, turnarounds etc.
Salary varies but a good ball park figure is probably about the £25K - £28K mark.
Your responsibilities vary with where you work. Too broad a spectrum to give a norm. Supervision wise, the tasks on your approval will be down to you! Other tasks you are given will be supervised by a 'B' licenced engineer.