Thank you Djbane, it was a previous post of yours that explained the digital and manual route.
At the post office I provided my passport number (since had a new one applying 10days after) and sons full birth certificate but when I tracked, there is a link for ‘what you need to send’ and this also asks for mine or dads birth certificate… not been asked for this and webchat just say nothing outstanding, waiting for examiner and they may ask for more info. I’ve ordered my full birth certificate just incase but won’t come till 15/6. Thanks again.