Home visit from midwife, 20weeks?

Katie • 23 from UK. Single mum to Mya. Born 4th Feb 2017 👶🏼💗
I just received a letter this morning saying a midwife will be coming to visit me in September, I'll be 20w+2 days pregnant, anyone else in the UK had this??  I have an appointment with my usual midwife next Tuesday I'm going to ask why someone is coming to visit me at home.