That's frustrating. at least it's still early! how did you even find this out? I was paranoid about this so I kept trying to casually mention the words "letterhead" and "signature" to my writers.
If you are going through interfolio or something like that, just have him re-upload it and then you can just select the new signed one when you go to submit the letters to your health professions committee.
If they were sent to the schools, just call the schools and ask them what to do.
Yeah...I had the same problem, but I didn't know about this aspect so I never told my writer about it.
In any case, I contacted him, and he re-uploaded a signed version the next day (there are several ways to sign, including a digital version through Interfolio that's quite fun). I just deleted the original and kept the signed version. You cal always call Interfolio to make sure it's signed and on letterhead.
Yeah luckily it just went to Interfolio and not to any schools...I still have some time..When you click on the document it tells you that it is not signed, so if you don't see anything you are good to go! I'll try to have him reupload it and hopefully that will work..