I have notified HMRC that I had started trading as self-employed on 5th March. I know I have to pay Class 2 National Insurance. I would like to pay it once a quarter. HMRC website says something about bills issued in April each year. Can I expect sucha a bill to reach me by post? What is the deadline to pay it? Also, do I have to register for NI Class 2 if I had already registered as self-employed using online form?