Recall of MPs Bill

This is also about knowing what the process would be to ensure that the signature being sent in is authentic. Since we had the change on applying for a postal vote, a signature and a date of birth is required, and I understand that the signatures are scanned and have to match. If someone has just written on small piece of paper that they want a recall and they send it in, is that good enough? How do we verify that the signature is from a legitimate person, one who might not have applied for a postal vote?