I was in the military years ago, even then a lot has been digitized, this would have been definitely transmitted digitally. Though it probably would have been sent over SIPR or something because it would be something classified to COs or maybe XO

I got tons of orders sent to my military email, PCS orders, directive changes, DoD notifications etc. and even an online portal where you could pull up your historical transmittals with your CAC card

Though a lot of internal command business is done with a mix of paper and digital, just about any communications between an individual command and DoD or “Big Air Force/Navy/Army/Marines” was done digitally