Yes you sign it and scan and upload that way if using webform that's what i understood from the letter they send. I did send like you did prior to letter without sign, and later read somewhere here this letter someone else posted too. that you have to sign and upload via web form. But you do not sign and upload if they ask in your account to upload.Same situation as yours...I got SA letter on 10th May still no correspondence to upload. I have uploaded today using web form and just typed my name and that's it...Do we have to print, handwritten the name and sign it and then scan and upload?
Are you also mailing or emailing them?