Student Finance England - uploading birth certificate

Hello!

I've recently sent in an application to SFE for a postgraduate loan for an International Relations course with a January intake at Teeside University. It's been a simple enough process, of course, but I've come across an issue in that my passport expired over a year ago, and as such I need to send my birth certificate instead. The SFE website tells me that I'm able to upload a digital copy of my birth certificate to verify instead, but I'm unable to find where exactly I'm supposed to do that. I know I can send it in via post, but I'd like to only leave that as a last resort if uploading digitally is still an option. So, some pointers as to where I should upload my birth certificate digitally. I hope I'm not just being blind.

Thanks for your time, and the help.