Pennsylvania

but here is the process - https://www.vote.pa.gov/Voting-in-PA/Pages/Mail-and-Absentee-Ballot.aspx

Here are snapshots of the forms -

MAIL-IN (NO EXCUSE)



ABSENTEE



Neither allows the official residence to be a P.O. box. BUT both forms have the option of "Where to mail the ballot" and THAT is where there is an option of designating that the ballot be sent to a P.O. box.

I know that one of the reasons that someone might have it mailed to a different location other than their primary residence is because they may have someone who is temporarily in a rehab facility and has a regular place of residence, but still wants to vote and won't be at their primary residence for receipt of the ballot, so the ballot can be sent to that temp location.

The main difference between them other than the no-excuse having the option to have the mail-in type be "annual" (for the rest of that year), is that for the absentee one, it is declaring that you "will be absent from your municipality" whereas the regular one does not require that to be the case. In the case for those who are working overseas (non-military as the base will have a P.O. box), there is a whole process for that which can also include emailing of the ballot for completion and mailing back - https://www.vote.pa.gov/Voting-in-PA/pages/military-and-overseas-voters.aspx

OVERSEAS /REGISTRATION AND ABSENTEE



However per the article, there may have also been the completion of the section "8" of the no excuse or section "B2" of the absentee that indicates "Help with this form", where the voter can designate a 3rd party to sign for them. And this may have happened if the unwitting voter provided the fraudster the other info for identification purposes (license #, SS#, etc) but never signed the form, and the fraudster completed that section as the 3rd party and put a "mark" in to represent the voter's "mark" to consent to it.

The article had several mentions of how there was "different handwriting" in different sections on the ballot request forms they did receive.