I would sign up for a Dropbox account. For the starter package it is free. Scanning your letter to Dropbox will e sure you ALWAYS have it no matter where you are at. All you need is an internet connection.
If I were you, I would make sure I have a copy on my person when I traveled outside of Pa. Just to be safe. Always keep documentation of when you left Pa such as a receipt for gas. I ALWAYS buy gas before I leave Pa AND as soon as I return to Pa. I get off at the first Pa exit and buy gas. Even if it’s only 1 gallon. This way no one can argue when I left and how long I was gone.
My GF says I am Parnoid but no way I am getting stuck in a different state and hoping a “hey guys I promise you I am legit” will get me out of jail because some cop decided it would be funny to lock up an out of state offender. Besides, I have family in NY and travel there frequently. I had one scary encounter in NY, but because I am registered in Pa and NY and had my receipts I was cleared to go back home. I probably would have won if it was pressed, but I didn’t want to find out.
Congrats and Good Luck, my friend